Dr. Jeff Masters' WunderBlog

Into the Storm: A book review

By: JeffMasters, 16:42 GMT le 25 février 2011

"Matt's compact Jeep became impossible to handle. Water rose on the road. We saw a family hiding in the nook of an overpass and decided that joining them was our best chance to escape danger. We parked the car and ran. Then the tornado ground straight in our direction. Thick tree branches snapped like bread sticks and made gunshot-style sounds that pierced the tornado's baritone howl. Mud flew everywhere. Air getting sucked into the tornado rushed through every seam in the overpass."

Meteorologist Reed Timmer, star of Discovery Channel's Storm Chasers, and writer Andrew Tilin have teamed up to write a highly entertaining and solidly educational book that is filled with gripping stories like this, detailing Timmer's amazing career as a storm-chasing meteorologist. Into the Storm begins in 1998, when Timmer enrolled as an undergraduate in the University of Oklahoma's meteorology program. His early chase stories leave one marveling that he is still alive, as his strong obsession to experience and learn about severe storms was not accompanied by much knowledge or common sense. The excerpt above is an account of his chase of the infamous F5 Bridge Creek, Oklahoma tornado of May 3, 1999--the strongest tornado ever measured, with Doppler-estimated winds of 302 mph. Timmer lucked out, as the tornado made a sudden turn and spared him its full fury. He goes on to explain in detail how taking shelter under an overpass in a tornado is a bad idea (the overpass can magnify the winds, you've elevated yourself into a region where surface friction is not slowing down the winds as much, and you're exposed to flying debris.)

Timmer's narrative of his encounter with the Bridge Creek tornado sets the tone for the book--chase stories interwoven with meteorological education. The meteorology is described in a way that a high school-educated person can understand, and is generally accurate and well-done (one exception: he fails to go into enough detail on how hurricanes get their energy, merely saying they get it from warm ocean waters.) Mixed in with the chase stories and meteorology lessons are details of Timmer's personal life, his past, and feelings about his severe weather fascination. These add a very human touch to the book that will make it appealing to a wide audience. A center eight-page section of color photos enhances the presentation, though I would have liked to see more photos illustrating the University of Oklahoma, the Storm Prediction Center, and the locations of the two dramatic hurricane chases told in the book. His chase stories of Hurricane Katrina (where he weathered the storm at the jail house in Slidell after getting arrested as a suspected looter), and Hurricane Floyd (where he spent the storm in a mobile home near the eyewall), are eye-poppingly insane. He also talks a good deal about the dilemma faced by many meteorologists--how to reconcile our passion for storms with the great suffering and destruction they wreak. He opens the book thusly:

"It's an interesting proposition, seeking happiness from tornadoes. For those few of us who are unquestionably mesmerized by them, chasing tornadoes can be the most fantastic experience in the world. Tornado chasing taxes your intellect and puts you at one with incredible, spectacular forces of nature. Chasing is also a fix for any adrenaline junkie and, if you do it often enough, can become your career. But an obsession with stalking tornadoes can kill or maim you too, and even if chasing doesn't leave you with physical scars or a need for crutches, it's hard to escape unscathed. You'll witness death and destruction of property that sickens your stomach and saddens your heart. Your family will worry about you. Significant others will tire of playing second fiddle. Peers will disagree with the way you chase, and you'll lose friends to your obsession."

Timmer achieves some degree of relief from this dilemma by realizing that storm chasers do a public service by calling in reports that lead to more accurate tornado warnings, saving lives. He is also dedicated to collecting data for tornado research using video and instrumented chase vehicles. Still, the dilemma of attempting to gain happiness from tornadoes is one Timmer does not entirely have the answers to, giving this book a human element often lacking in books written by scientists. I recommend Into the Storm to both scientists and non-scientists; the stories are amazing, and the science is presented in a non-obtrusive way that does not slow down the book, but instead enhances it. Teaching meteorology using stories is a great way to educate people, and Timmer has done a great service to the field of meteorology by writing this book. Three and a half out of four stars. Into the Storm is $16.33 (hardback) from amazon.com. The amazon website and Timmer's tornadovideos.net website also have a spectacular 2-minute video clip highlighting some of the chases documented in the book.

This review will appear later this year in the Bulletin of the American Meteorological Society, and is Copyright 2011 American Meteorological Society (AMS). Permission to use figures, tables, and brief excerpts from this work in scientific and educational works is hereby granted provided that the source is acknowledged. Any use of material in this work that is determined to be "fair use" under Section 107 of the U.S. Copyright Act September 2010 Page 2 or that satisfies the conditions specified in Section 108 of the U.S. Copyright Act (17 USC ?108, as revised by P.L. 94-553) does not require the AMS's permission. Republication, systematic reproduction, posting in electronic form, such as on a web site or in a searchable database, or other uses of this material, except as exempted by the above statement, requires written permission or a license from the AMS. Additional details are provided in the AMS Copyright Policy, available on the AMS Web site located at (http://www.ametsoc.org/) or from the AMS at 617-227-2425 or copyright@ametsoc.org.

Wunderground hiring a climate scientist
Weather Underground, Inc. is seeking a full-time scientist with excellent communication and programming skills to improve our climate change and meteorology education web pages. Initial task: use downscaled climate model output to generate "far-future" forecasts. The position requires an M.S. or Ph.D. in meteorology. Consult our employment web page for a full job description and application info. The increase in significant weather events over the past year has kept me tied up blogging, giving me little time to work on expanding the content of our climate change and weather education web pages. It is time to get some help!

Jeff Masters

Book and Movie Reviews

Updated: 19:16 GMT le 01 Mars 2011

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Drought in China adds pressure to world food prices

By: JeffMasters, 02:49 GMT le 23 février 2011

The soil lies cracked and broken in China's Shangdong Province, thirsting for rains that will not come. China's key wheat producing region, lying just south of Beijing, has received just 12 millimeters (1/2 inch) of rain since September, according to the Chinese news service Xinhua. If no rains come during the remainder of February, it could become the worst drought in 200 years. The latest precipitation forecast from the GFS ensemble model predicts the possibility of rains of around 1/2 inch for Shandong Province early next week, but these rains would help only a little. A longer-range 2-week forecast from the operational GFS model shows little or no rain for the region from late next week well into March. Columbia University's International Research Institute for Climate and Society (IRI) projects that spring in Eastern China has an enhanced probability of being dry, with only a 20% - 25% chance that the region will see above average precipitation, and a 40% - 45% chance of below average precipitation. So the great drought will likely continue, and China's ability to feed itself may be greatly challenged this year.


Figure 1. A dried cornfield in a mountainous area of Jinan, capital of east China's Shandong Province, Jan. 18, 2011. Image credit: Xinhua/Zhu Zheng.


Figure 2. Drought conditions in China's Shandong Province this February have reached the "Severe" category. Image credit: Beijing Climate Center.

Impact on global food supplies and food prices
According to the Food and Agriculture Organization of the United Nations (FAO), the drought in north China seems to be putting pressure on wheat prices, which have been rising rapidly in the past few months. This has helped push global food prices to their highest levels since the FAO Food Price Index was created in 1990 (Figure 3.) China is the world's largest producer of wheat, and if they are forced to import large amounts of food due to continued drought, it could severely impact world food prices. However, the FAO's regional representative for Asia and the Pacific said in an interview with Reuters last month that the situation is not as severe as in 2008, when global food riots erupted. "In general, the supply/demand situation of food grains has become very tight at the moment but enough stocks means there is no cause for alarm," Konuma said. "We still maintain sufficient stocks, which is about 25 percent of annual production. As long as there are sufficient stocks, that means the world has enough food still to feed the people." However, he said that if food stocks continued to decline over the next few years, there would be cause for concern.

The record food global food prices have been partially driven by two other huge weather disasters, the Russian summer heat wave and drought of 2010, and the Australian floods of December - January 2011. Both Russia and Australia are major exporters of grain. Russia issued a ban last summer on grain exports because of their drought, which slashed the wheat harvest by 40% and damaged soils to such an extent that 10% of Russian wheat fields could not be planted this year. The Russian heat wave of 2010 is now estimated by the Centre for Research on the Epidemiology of Disasters to be the deadliest in human history, with 55,736 deaths. The Australian floods caused at least $1.7 billion in agricultural damage, reducing their wheat crop significantly. Fortunately, bumper crops were harvested in non-flooded areas of Australia, and the winter crop harvest in country was up 19% over the previous year's crop, and was the biggest since 2003 - 2004. Australia has been struggling with severe drought in recent years that caused more agricultural damage than the floods did.


Figure 3. The global price of food between 1990 - January 2011, as measured by the U.N.'s FAO Food Price Index. The FAO Food Price Index is a measure of the monthly change in international prices of a basket of food commodities. It consists of the average of price indices for Cereals, Oils and Fats, Sugar, Dairy, and Meat, weighted by the average export shares of each group. Food prices between 2002 - 2004 are given a benchmark value of "100". Global food prices in January 2011 were the highest since the FAO Index was established in 1990. Image credit: Food and Agriculture Organization of the United Nations.

Drought outlook for Northern Hemisphere summer of 2011
The spike in global food prices this winter raises the concern that a severe drought in a major grain producing region in North America, Europe, or Asia this summer could severely impact grain supplies and food prices. Fortunately, with La Niña conditions over the Eastern Pacific weakening, and possibly abating by summer, the chances for such a drought are lower than they would have been if La Niña were to stay strong into the summer. The latest precipitation forecast from Columbia University's International Research Institute for Climate and Society (Figure 4) shows few areas of drought concern for the coming Northern Hemisphere summer. However, our skill at predicting drought months in advance is limited. For example, IRI's February 2010 forecast of precipitation for the summer of 2010 did not highlight Russia as an area of possible concern for drought, and Russia ended up having one of its worst droughts in history. IRI did highlight the Amazon as a region likely to have below-average summer rains, though, and the Amazon ended up having a 100-year drought last summer.


Figure 4. Global precipitation forecast for June, July and August of 2011, made in February 2011. Only a few scattered regions of the globe are predicted to have above-average chances of drought (yellow colors.) These areas include the Northwest U.S., Southern Brazil, and Northwest China. Image credit: International Research Institute for Climate and Society

Commentary
The recent unrest in the Middle East, which has been attributed, in part, to high food prices, gives us a warning of the type of global unrest that might result in future years if the climate continues to warm as expected. A hotter climate means more severe droughts will occur. We can expect an increasing number of unprecedented heat waves and droughts like the 2010 Russian drought in coming decades. This will significantly increase the odds of a world food emergency far worse than the 2007 - 2008 global food crisis. When we also consider the world's expanding population and the possibility that peak oil will make fertilizers and agriculture much more expensive, we have the potential for a perfect storm of events aligning in the near future, with droughts made significantly worse by climate change contributing to events that will cause disruption of the global economy, intense political turmoil, and war.

I will be doing another post on Thursday or Friday.

The New York Times' Andy Revkin in his Dot Earth Blog has a more in-depth look at the food and climate change issue that I recommend.

Jeff Masters

Drought

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Dakotas blizzard adds to extreme spring flooding risk

By: JeffMasters, 02:13 GMT le 21 février 2011

Heavy snows in excess of six inches have piled up over much of South Dakota, North Dakota, Montana, Wisconsin, and Minnesota today, with a storm maximum of 16 inches reported at Midland, South Dakota. This is bad news for residents in flood-prone areas of the Upper Midwest, as the new storm has added more than another half inch of melted rainfall equivalent to a snowpack that already had a record water content. When all that snow melts in late March, we can expect another spring of major and possibly record flooding for North Dakota, South Dakota, Minnesota, or the Upper Mississippi River north of St. Louis, according to the National Weather Service (NWS). Their February Spring Flood Outlook released last week warned: "Heavy autumn rains and above average water content in the snow pack throughout the North Central U.S. have produced a high risk of moderate and major flooding for the Spring of 2011. Areas of greatest concern include the Red River of the North in North Dakota and Minnesota, Devils Lake in North Dakota, the James River and Big Sioux River in South Dakota, and areas along the Upper Mississippi River including Minnesota, Wisconsin, Iowa, Illinois and Missouri.

Heavy late summer and autumn precipitation (twice the normal amount since October in parts of North Dakota and Minnesota) have soils saturated and streams running high before the winter freeze-up. Another winter of above average snowfall has added water to the snow pack on top of the frozen saturated soils in the North Central US. NWS models show this snowpack containing a water content ranked in the 90 to 100 percentile when compared to a 60 year average. These factors have combined to create some of the highest soil moisture contents of the last century. "



Figure 1. North Central U.S. flood risk. Image credit: NWS. The outlook will be updated on February 24, and a final outlook issued March 17.

There is a huge amount of snow on the ground in North Dakota along the tributaries of the Red River, thanks to fall precipitation that was 150% - 300% of normal, and winter snows that have dumped up to 400% more precipitation than usual. If one were to melt this snow, it would amount to 4 - 5 inches of rain. If heavy rains occur at the same time that the snow melts, there is the potential for the greatest flood in history to affect the cities of Fargo and Grand Forks, the largest and third largest cities in North Dakota. NWS is giving a 20% chance that Fargo will see its greatest flood in history, and a 10% chance for Grand Forks.

The situation is similar in Minnesota, which has received about double its normal precipitation over the past 3 to 4 months. Snow depths are generally around 18 inches in the Upper Mississippi watershed, with a high water content. If one were to melt this snow, it would amount to 3.5 - 5.5 inches of rain, which ranks among the wettest snow packs in the 60-year record. NWS is giving a 15% chance that St. Paul will see its highest flood in history this spring.

In South Dakota, heavy snows this winter have also left a snowpack with a high water content, and NWS is predicting a 30% chance that the the James River at Huron, SD and the Big Sioux River at Brookings, SD will reach their highest flood heights in history.


Figure 2. The snow water equivalent of the Upper Midwest's snowpack as of February 18, 2011. Large sections of Minnesota and North Dakota have the equivalent of 3.9 - 5.9 inches of rain (purple colors) stored in their snowpack. Image credit: NWS/NOHRSC.

When will all this flooding occur? Generally, late March through mid-April is the time when the big spring melt occurs. The record 2009 Red River flood peaked on March 28 in Fargo. The great 1997 Red River flood that devastated Grand Forks, causing $3.5 billion in damage, crested on April 18. St. Paul's greatest flood in history crested on April 19, 1965.

I'll have a new post Tuesday or Wednesday.

Jeff Masters

Flood Winter Weather

Updated: 02:19 GMT le 21 février 2011

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January global temperatures 11th - 17th warmest on record

By: JeffMasters, 14:14 GMT le 18 février 2011

January 2011 was the globe's 17th warmest January on record, according to the National Oceanic and Atmospheric Administration (NOAA) National Climatic Data Center (NCDC). NASA's Goddard Institute for Space Studies rated January the 11th warmest on record. January 2011 global ocean temperatures were the 11th warmest on record, and land temperatures were the 29th warmest on record. Global satellite-measured temperatures for the lowest 8 km of the atmosphere were average,the 16th or 17th coolest in the 34-year record, according to Remote Sensing Systems and the University of Alabama Huntsville (UAH). The global cool-down from November, which was the warmest November on record for the globe, was due in large part to the on-going moderate strength La Niña episode in the Eastern Pacific. The large amount of cold water that upwells to the surface during a La Niña typically causes a substantial cool-down in global temperatures. Notably, the January 2011 global ocean temperature was the warmest on record among all Januaries when La Niña was present. The ten warmest Januaries occurred during either El Niño or neutral conditions.


FIgure 1. Departure of temperature from average for January 2011. Image credit: National Climatic Data Center (NCDC).

The coldest places on the globe in January, relative to average, were Mongolia, Southern Siberia, and China. China recorded its coldest January since 1977, and second coldest January since national records began in 1961. Record or near-record warm conditions were experienced in Northeast Canada, Western Greenland and Northern Siberia.

A cold and dry January for the U.S.
For the contiguous U.S., January temperatures were the 37th coldest in the 116-year record, and it was the coldest January since 1994, according to the National Climatic Data Center. Despite the heavy snows in the Northeast U.S., January was the 9th driest January since 1895. This was largely due to the fact that the Desert Southwest was very dry, with New Mexico recording its driest January, and Arizona and Nevada their second driest.

Sea ice extent in the Arctic lowest on record during January
January 2011 Northern Hemisphere sea ice extent was the lowest on record in January, according to the National Snow and Ice Data Center. This was the second consecutive month of record low extent. Satellite records extend back to 1979. The area of missing ice was about twice the size of Texas, or 60% the size of the Mediterranean Sea. Ice was notably absent in Northeast Canada and Western Greenland, and Hudson Bay did not freeze over until mid-January, more than a month later than usual. This was the latest freeze-up on record, and led to record warmth over much of Northeast Canada. Frobisher Bay on Baffin Island had its warmest January on record, 1.1°C above the previous record set in 1985. Weather records for the station go back to 1942.

An incredible 110° temperature swing in 1 week in Oklahoma
The temperature in Bartlesville, Oklahoma shot up to a record 82°F yesterday, just seven days after the city hit -28°F on February 10. This 110°F temperature change has to be one of the greatest 1-week temperature swings in U.S. history. The -31°F that was recorded in nearby Nowata last week has now been certified by the National Weather Service as the new official all-time coldest temperature ever recorded in Oklahoma. What's more, the 27 inches of snow that fell on Spavinaw, Oklahoma during the February 8 - 9 snowstorm set a new official state 24-hour snowfall record. The previous record was 26", set on March 28, 2009, in Woodward and Freedom.

A 100+ degree temperature change in just six days is a phenomenally rare event. I checked the records for over twenty major cities in the Midwest in Oklahoma, Texas, Kansas, Wyoming, Nebraska, South Dakota, North Dakota, and Montana, and could not find any examples of a 100-degree temperature swing in so short a period of time. The closest I came was a 108° swing in temperature in fourteen days at Valentine, Nebraska, from -27°F on March 11, 1998 to 82°F on March 25, 1998. Valentine also had a 105°F temperature swing in fifteen days from November 29, 1901 (71°F) to December 14, 1901 (-34°F.) Our weather historian, Christopher C. Burt, lists the world record for fastest 24-hour change in temperature as the 103°F warm-up from -54° to 49° that occurred on January 14 - 15, 1972, during a chinook wind in Lowe, Montana. This week's remarkable roller coaster ride of temperatures in Oklahoma is truly a remarkable event that has few parallels in recorded history.

Tropical Cyclone Carlos' deluge abates
Darwin, Australia suffered its greatest 24-hour rainfall in its history on Wednesday, when a deluge of 13.4 inches (339.4 mm) hit the city when Tropical Cyclone Carlos formed virtually on top of city and remained nearly stationary. Carlos has now dissipated, and brought only an additional 1.50" (38 mm) of rain yesterday to Darwin. Over the past four days, Carlos has dumped a remarkable 26.87" (682.6 mm) of rain on Darwin (population 125,000), capital of Australia's Northern Territory. Australia's west coast is also watching Tropical Cyclone Dianne, which is expected to remain well offshore as it moves southwards, parallel to the coast.


Figure 2. Solar flare of February 15, 2011, as captured by the SOHO and SDO spacecraft. Image credit: NASA.

Space weather: biggest solar flare in 4 years
The strongest solar flare in more than four years erupted on the sun at 0156 UTC on Tuesday, when giant sunspot 1158 unleashed an X2-class eruption. X-class flares are the strongest type of x-ray flare, and this week's flare is the first X-class flare of the new 11-year sunspot cycle 24, which began in 2009 - 2010. The flare was accompanied by a Coronal Mass Ejection (CME), which means that a portion of the sun's atmosphere was ripped away and thrown into space. High-energy particles from the CME arrived at Earth at 01 UTC this morning, and sky watchers at high northern latitudes may be able to see auroras over the coming few nights. Consult NOAA's Space Weather Prediction Center or spaceweather.com for updates.

Jeff Masters

Climate Summaries

Updated: 18:52 GMT le 18 février 2011

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-28° to 72° in 6 days: a wild ride in Oklahoma

By: JeffMasters, 15:09 GMT le 17 février 2011

The plants and animals of northeast Oklahoma are officially freaking out. Cold air pouring in behind last week's remarkable snowstorm over northeast Oklahoma brought unprecedented cold to the state on February 10, with a bone-chilling -31°F recorded at Nowata and -28°F at Bartlesville. These were the coldest temperatures ever measured in Oklahoma. But what a difference a week makes! Yesterday afternoon, just six days after experiencing -28°F, Bartlesville hit 72°F--an incredible 100°F temperature swing in just six days. Nearby Ponca City, which hit -25°F six days previously, hit 75°F yesterday, also achieving a 100°F temperature swing in just six days.


Figure 1. Record snows of 25" piled up in northeast Oklahoma near Afton on February 9, 2011. The fresh coasting of snow, which is a very excellent emitter of infrared radiation to space, enabled temperatures in Northeast Oklahoma to plunge to record lows on the morning of February 10. Image credit: wunderphotographer Bladerider.

A 100+ degree temperature change in just six days is a phenomenally rare event. I checked the records for over twenty major cities in the Midwest in Oklahoma, Texas, Kansas, Wyoming, Nebraska, South Dakota, North Dakota, and Montana, and could not find any examples of a 100-degree temperature swing in so short a period of time. The closest I came was a 108° swing in temperature in fourteen days at Valentine, Nebraska, from -27°F on March 11, 1998 to 82°F on March 25, 1998. Valentine also had a 105°F temperature swing in fifteen days from November 29, 1901 (71°F) to December 14, 1901 (-34°F.) Our weather historian, Christopher C. Burt, lists the world record for fastest 24-hour change in temperature as the 103°F warm-up from -54° to 49° that occurred on January 14 - 15, 1972, during a chinook wind in Lowe, Montana. This week's remarkable roller coaster ride of temperatures in Oklahoma is truly a remarkable event that has few parallels in recorded history.

Darwin sets its all-time 24-hour rainfall record
Darwin, Australia suffered its greatest 24-hour rainfall in its history on Wednesday, when a deluge of 13.4 inches (339.4 mm) hit the city when Tropical Cyclone Carlos formed virtually on top of city and remained nearly stationary. Over the past three days, Carlos has dumped a remarkable 25.37" (644.6 mm) of rain on the Darwin (population 125,000), capital of Australia's Northern Territory. Carlos has moved slowly inland today, and continues to dump rain on Darwin, but these rains will gradually subside over the next few days as the storm weakens and moves farther inland. Not surprisingly, the rains have triggered major flooding in the Darwin area. The heavy rains in Darwin are due to the very slow motion of the storm, which has been able to keep a significant portion of its circulation over the warm 30°C (86°F) waters off the coast. These water temperatures are near normal for this time of year. Australia's west coast is also watching Tropical Cyclone Dianne, which is expected to remain offshore as it moves southwards, parallel to the coast.


Figure 2. Radar image of Tropical Cyclone Carlos taken at 14:35 UTC on February 17, 2011. Spiral bands from Tropical Storm Carlos were rotating clockwise onto shore near Darwin, adding to that city's record rainfall totals. Image credit: Australia Bureau of Meteorology.



Carlos' deluge add to the misery of flood-weary Australia, which has suffered from some of its greatest natural disasters in history in 2011. Earlier this month, Category 4 Tropical Cyclone Yasi smashed into Queensland with 155 mph winds, making it the strongest hurricane to hit Queensland since at least 1918. Yasi was the second most expensive tropical cyclone ever to hit Australia, with damages currently estimated near $3 billion. Australia is still reeling from torrential deluges that affected the states of Queensland and Victoria November - January, triggering flooding that caused the most expensive natural disaster in Australian history. Damage estimates of the flood are speculative, but range from $10 - $30 billion. The floods were spawned by the rainiest September - November (spring) and December in Queensland's history, driven in part by La Niña-enhanced sea surface temperatures along the coast that were the warmest on record. However, all rivers in the flooded eastern half of Queensland have now fallen below flood level. Rainfall amounts in the coming week are expected to be in the 1 - 4 inch range, which should not cause any significant new flooding problems.

Tropical Cyclone Bingiza makes a 2nd landfall in Madagascar
On Monday, Tropical Cyclone Bingiza roared ashore over Northern Madagascar as a dangerous Category 3 hurricane with 115 mph winds. The storm is being blamed for six deaths, has left 15,000 homeless, and has destroyed 8,500 buildings. After re-emerging over the waters of the Mozambique Channel between Africa and Madagascar on Tuesday, Bingiza re-intensified, and made a second landfall along the southwest coast of Madagascar early today as a tropical storm. Bingiza is expected to dissipate over Madagascar tomorrow, but not before dumping very heavy rains capable of causing additional flooding problems on Madagascar's deforested mountain slopes.


Figure 3. Visible satellite image of Tropical Cyclone Bingiza making its second landfall over Madagascar at 14 UTC on February 17, 2011. Image credit: Navy Research Lab, Monterey.

Bingiza is just the second tropical cyclone in the Southwest Indian Ocean (west of 90E) during the 2010 - 2011 season; this is an unusually low amount of activity for the basin. According to an email I received from Sebastien Langlade of the tropical cyclone forecasting office on La Reunion Island, January 2011 was the first January since accurate records began in 1998 that the Southwest Indian Ocean failed to record a single tropical storm. The only other storm in the basin so far this season has been Tropical Cyclone Abele (29 Nov - 4 Dec 2010), a Category 1 storm that stayed out to sea. Bingiza was the 4th major (Category 3 or stronger) tropical cyclone world-wide this year.

Jeff Masters

Winter Weather

Updated: 16:17 GMT le 17 février 2011

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La Niña weaker; may be gone by summer

By: JeffMasters, 16:03 GMT le 15 février 2011

A significant shift is occurring in the Equatorial waters of the Eastern Pacific off the coast of South America, where the tell-tale signs of the end to the current La Niña event are beginning to show up. A borderline moderate/strong La Niña event has been underway since last summer, with sea surface temperatures (SSTs) about 1.5°C below average over a wide stretch of the Equatorial Pacific. These cool SSTs have altered the course of the jet stream and have had major impacts on the global atmosphere. The La Niña has been partially responsible for some of the extreme flooding events in recent months, such as the floods in Australia, Sri Lanka, and Colombia. La Niña is also largely to blame for the expanding drought over the southern states of the U.S. But in the last few weeks, SSTs in the Equatorial Pacific have undergone a modest warm-up, and these temperatures are now about 1.2°C below average. A region of above-average warmth has appeared immediately adjacent to the coast of South America--often a harbinger of the end to a La Niña event. An animation of SSTs since late November shows this developing warm tongue nicely. Springtime is the most common time for a La Niña event to end; since 1950, half of all La Niñas ended in March, April, or May. The weakness displayed by the current La Niña event has prompted NOAA's Climate Predictions Center to give a 50% chance that La Niña will be gone by June. If La Niña does rapidly wane, this should help reduce the chances for a continuation of the period of high-impact floods and droughts that have the affected the world in recent months.


Figure 1. A comparison of the the departure of sea surface temperature (SST) from average between this week and two months ago shows that a tongue of warmer-than-average waters has appeared off the coast of South America, possibly signaling the beginning of the end of the current La Niña event. Image credit: NOAA Climate Prediction Center.

What does this mean for hurricane season?
As many of you know, the phase of the El Niño/La Niña is critical for determining how active the Atlantic hurricane season is. La Niña or neutral conditions promote very active Atlantic hurricane seasons, while El Niños sharply reduce Atlantic hurricane activity, by increasing wind shear. Will the probable demise of La Niña this spring allow an El Niño to take its place by this fall? Well, don't get your hopes up. Since 1950, NOAA's Climate Prediction Center records that there have been sixteen La Niña events during February (26% of all years.) In half of those years, La Niña was still active during the August - September - October peak of Atlantic hurricane season, six (38%) transitioned to neutral conditions, and only two (12%) made it all the way to El Niño. So historically, the odds do not favor a transition to El Niño by hurricane season. The latest set of computer model forecasts of El Niño/La Niña (Figure 2) also reflect this. Only two of the sixteen models predict El Niño conditions by hurricane season.


Figure 2. Predictions made in January 2011 of the evolution of El Niño/La Niña over the coming year shows that only two of the sixteen models predict El Niño conditions by hurricane season, while four predict La Niña and ten predict neutral conditions. Image credit: Columbia University IRI.

I'll have a new post by Thursday.

Jeff Masters

Climate Summaries

Updated: 16:05 GMT le 15 février 2011

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Category 3 Bingiza hits Madagascar

By: JeffMasters, 13:25 GMT le 14 février 2011

Tropical Cyclone Bingiza roared ashore over Northern Madagascar early today as a dangerous Category 3 hurricane with 115 mph winds. Recent microwave imagery from NASA's TRMM satellite shows that Bingza had a large region of heavy rains of 0.4 - 0.7 inches per hour in the eyewall and inner spiral bands at landfall. Rainfall amounts of up to 8 inches are being predicted along Bingza's path over northern Madagascar for the coming 24 hours by NOAA's automated tropical cyclone rainfall prediction system. Rains of this magnitude are capable of causing dangerous flooding in Madagascar, and the storm's winds and storm surge likely caused serious damage in the moderately populated area where the storm came ashore. Bingiza will weaken today as it traverses the island, but is expected to re-intensify once it emerges over the Mozambique Channel between Africa and Madagascar on Tuesday, where sea surface temperatures are about 0.4°C above average. As the storm skirts the western coast of Madagascar Tuesday and Wednesday, the island will receive additional very heavy rains on its mountainous slopes. Madagascar suffers from extensive deforestation, and a storm like Bingiza is capable of causing very dangerous floods.


Figure 1. True color satellite image of Tropical Cyclone Bingiza as it approached landfall in Madagascar at 07 UTC on February 13, 2011. Image credit: NASA.

Bingiza is just the second tropical cyclone in the Southwest Indian Ocean (west of 90E) during the 2010 - 2011 season; this is an unusually low amount of activity for the basin. The only other storm so far this season has been Tropical Cyclone Abele (29 Nov - 4 Dec 2010), a Category 1 storm that stayed out to sea. Bingiza is the 4th major (Category 3 or stronger) tropical cyclone world-wide this year.

Jeff Masters

Hurricane

Updated: 13:27 GMT le 14 février 2011

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Another amazingly snowy winter for the U.S.

By: JeffMasters, 15:18 GMT le 11 février 2011

As northeast Oklahoma and northwest Arkansas dig out from the two feet of snow dumped this winter's latest epic snowstorm, it's time to summarize how remarkable the snows of the past two winters have been. So far this winter, the Northeast U.S. has seen three Category 3 (major) or higher snow storms on the Northeast Snowfall Impact (NESIS) scale. This scale, which rates Northeast snowstorms by the area affected by the snowstorm, the amount of snow, and the number of people living in the path of the storm, runs from Category 1 (Notable) to Category 5 (Crippling.) This puts the winter of 2010 - 2011 in a tie for first place with the winters of 2009 - 2010 and 1960 - 1961 for most major Northeast snowstorms. All three of these winters had an extreme configuration of surface pressures over the Arctic and North Atlantic referred to as a negative North Atlantic Oscillation (NAO) and Arctic Oscillation (AO). In this situation, the band of winds that circles the North Pole weakens, allowing cold air to spill southwards into the mid-latitudes.

In the past twelve months, we've had six major Category 3 or stronger storms on the NESIS scale, by far the most major snowstorms in a 12-month period in the historical record. Going back to 1956, only one 12-month period had as many as four major snowstorms--during 1960 - 1961. New York City has seen three of its top-ten snowstorms and the two snowiest months in its 142-year history during the past 12 months--February 2010 (36.9") and January 2011 (36.0"). Philadelphia has seen four of its top-ten snowstorm in history the past two winters. The Midwest has not been left out of the action this year, either--the Groundhog's Day blizzard nailed Chicago with its 3rd biggest snowstorm on record. According to the National Climatic Data Center, December 2010 saw the 7th greatest U.S. snow extent for the month in the 45-year record, and January 2011 the 5th most. December 2009 had the greatest snow extent for the month in the 45-year record, January 2010 the 6th most, and February 2010 the 3rd most. Clearly, the snows of the past two winters in the U.S. have been truly extraordinary.


Figure 1. The six major Category 3 Northeast snowstorms of the past twelve months. Image credit: National Climatic Data Center.

A cold January in the U.S.
January 2011 was the coldest January in the contiguous U.S. since 1994, according to the National Climatic Data Center, and ranked as the 37th coldest January in the 117-year record. Despite the heavy snows in the Northeast U.S., January was the 9th driest January since 1895. This was largely due to the fact that the Desert Southwest was very dry, with New Mexico recording its driest January, and Arizona and Nevada their second driest.

A cold and record snowy winter (yet again!) in the U.S. does not prove or disprove the existence of climate change or global warming, as we must instead focus on global temperatures averaged over decades. Globally, January 2011 was the 11th warmest since 1880, but tied for the second coolest January of the past decade, according to NASA. NOAA has not yet released their stats for January. The cool-down in global temperatures since November 2010, which was the warmest November in the historical record, is largely due to the temporary cooling effect of the strong La Niña event occurring in the Eastern Pacific. This event has cooled a large portion of the surface waters in the Pacific, leading to a cooler global temperature.

Some posts of interest I've done on snow and climate change over the past year:

Hot Arctic-Cold Continents Pattern is back (December 2010)
The future of intense winter storms (March 2010)
Heavy snowfall in a warming world (February 2010)

Have a great weekend, everyone, and enjoy the coming warm-up, those of you in the eastern 2/3 of the country!

Jeff Masters

Winter Weather

Updated: 15:19 GMT le 11 février 2011

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Oklahoma's coldest morning on record: -31°F ; storm leaves 2 feet of snow

By: JeffMasters, 14:13 GMT le 10 février 2011

Cold air pouring in behind yesterday's remarkable snowstorm over northeast Oklahoma has brought unprecedented cold to the state this morning, with a bone-chilling -31°F recorded at Nowata and -28°F at Bartlesville. These are the coldest temperatures ever measured in Oklahoma. According to Extreme Weather, the excellent weather records book by wunderground's weather historian, Christopher C. Burt, the previous coldest temperature in Oklahoma was -27°F set in nearby Watts on January 18, 1930. A personal weather station in nearby Hogshooter Valley also hit -28°F this morning (one wonders how the Valley got its colorful name!) Today's record is the second time since the year 2000 that one of the 50 states has set an all-time extreme cold temperature record. On January 16, 2009, Big Black River, Maine set a new state record with -50°F. In comparison, three states--Virginia, California, and South Dakota--have set all-time extreme heat records since 2000. Since 1990, nine states have set all-time extreme high temperature records, and eight states have set all-time extreme cold records. It was also very cold in Arkansas this morning, with a -20°F reading in Springdale. The all-time coldest temperature for Arkansas is -29°F, recorded on February 13, 1905, at Pond and Gavette. Relief is in sight, though--Tuesday's forecast calls for high temperatures in Bartlesville in the low 60s, a full 90 degrees warmer than this morning's low!


Figure 1. Record snows of 25" piled up in northeast Oklahoma near Jay on February 9, 2011. Image credit: wunderphotographer okieski.

Yesterday's major snowstorm blasted northeast Oklahoma, northwest Arkansas, and southwest Missouri with up to two feet of snow. The heaviest snows fell in northeast Oklahoma, with 25 inches reported at Jay. Siloam Springs in northwest Arkansas had 24.5", which is just 1/2" shy of the Arkansas state record for heaviest snowstorm of all-time, the 25" that fell on Corning on January 22, 1918. Yesterday's storm brought heavy snows of a foot or more to Kansas, Texas, Missouri, New Mexico, Colorado, Montana, and Wyoming, according the the latest NOAA Storm Summary. Significant snows also hit much of the Southeast, with 4.5" recorded in Vernon, AL; 3.8" in Memphis, TN; 3.7" in Bowling Green, KY; and 1" in Asheville, NC. The snow has almost ended over the Southeast, as the storm is now centered off the North Carolina coast and is moving out to sea.

Snowiest month and year in Tulsa's history
The 6.2 inches of snow that fell in Tulsa, Oklahoma during yesterday's snowstorm gave that city its snowiest month on record, according to the National Weather Service. Tulsa has received 23" of snow this month, most of this in the February 1 blizzard. The previous record snowiest month was March 1924, when 19.7" fell. The total for the 2010 - 2011 season now stands at 26.6", a new record. The previous record was the 25.6" that fell in the winter of 1923 - 1924. Oklahoma City received 5.9" of snow, bringing their seasonal total to 19.6", still well shy of their all-time record of 25.2", set in 1947 - 1948.


Figure 2. Snowfall amounts in Western Oklahoma and Northwest Arkansas from the snowstorm of Feb 8 - 9, 2011, reached two feet (24 inches) in isolated regions. Image credit: National Weather Service, Tulsa.

Jeff Masters

Winter Weather

Updated: 19:45 GMT le 10 février 2011

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WInter storm dumps 2 feet of snow on Oklahoma, Arkansas

By: JeffMasters, 20:25 GMT le 09 février 2011

Yet another major snowstorm in the memorable winter of 2010-2011 has blasted the U.S. with over two feet of snow--this time in northeast Oklahoma and northwest Arkansas. The snow continues to pile up at a rate of an inch per hour across portions of Arkansas today, and snows of 1 - 4 inches are expected today through Thursday across northern Mississippi, northern Alabama, and Tennessee. The heaviest snows have fallen in northeast Oklahoma, with 25 inches reported at Jay. Several locations in northwest Arkansas, including Gravette in Benton County, have recorded 24" of snow. Heavy snows in excess of a foot have been reported in Kansas, New Mexico, Colorado, Montana, and Wyoming, according the the latest NOAA Storm Summary. Bitterly cold air is pouring in behind the snowstorm; Abieline, Texas set a record low for the date of 9°F this morning, and the temperature is expected to plunge to 5°F tonight in the city. Abilene's coldest February temperature of all time was -7°F, set February 2, 1985.


Figure 1. Record snows piling up in northwest Arkansas on February 9, 2011. Image credit: wunderphotographer breezyky26.

Snowiest month and year in Tulsa's history
The 5.7 inches of snow that has fallen in Tulsa, Oklahoma as of noon today has brought that city its snowiest month on record, according to the National Weather Service. Thanks to the great February 1 blizzard and today's snowstorm, Tulsa has recorded 22.5" of snow this month. The previous record snowiest month was March 1924, when 19.7" fell. Today's snow brought the total for the 2010 - 2011 season to 26.1", a new record. The previous record was the 25.6" that fell in the winter of 1923 - 1924. Oklahoma City received 5.9" of snow from today's storm, bringing their seasonal total to 19.6", still well shy of their all-time record of 25.2", set in 1947 - 1948.


Figure 2. Snowfall amounts in Western Oklahoma and Northwest Arkansas from the snowstorm of Feb 8 - 9, 2011, reached two feet (24 inches) in isolated regions. Image credit: National Weather Service, Tulsa.

Jeff Masters

Winter Weather

Updated: 20:47 GMT le 09 février 2011

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Arctic sea ice at a record low again; a warmer February for the U.S. coming

By: JeffMasters, 13:42 GMT le 08 février 2011

Arctic sea ice extent for January 2011 was the lowest on record for the month, and marked the second consecutive month a record low has been set, according to the National Snow and Ice Data Center. Most of the missing ice was concentrated along the shores of Northeast Canada and Western Greenland. Relative to the 1979 - 2000 average, the missing ice area was about twice the size of Texas, or about 60% of the size of the Mediterranean Sea. Hudson Bay in Canada did not freeze over until mid-January, the latest freeze-up date on record, and at least a month later than average. The late freeze-up contributed to record warm winter temperatures across much of the Canadian Arctic in December and January. Bob Henson of the National Center for Atmospheric Research has a very interesting post on this, noting that Coral Harbor on the shores of Hudson Bay had a low temperature on January 6 that was 30°C (54°F) above average--a pretty ridiculous temperature anomaly. He quotes David Phillips, a senior climatologist with Environment Canada, who discussed the lack of ice near Canada's Baffin Island: "The Meteorological Service of Canada was still writing marine forecasts as of 7 January, well beyond anything we have ever done." Henson also writes:

"The extremes have been just as impressive when you look high in the atmosphere above these areas. Typically the midpoint of the atmosphere's mass--the 500-millibar (500 hPa) level--rests around 5 kilometers (3 miles) above sea level during the Arctic midwinter. In mid-December, a vast bubble of high pressure formed in the vicinity of Greenland. At the center of this high, the 500-mb surface rose to more than 5.8 kilometers, a sign of remarkably mild air below. Stu Ostro (The Weather Channel) found that this was the most extreme 500-mb anomaly anywhere on the planet in weather analyses dating back to 1948.

Farther west, a separate monster high developed over Alaska in January. According to Richard Thoman (National Weather Service, Fairbanks), the 500-mb height over both Nome and Kotzebue rose to 582 decameters (5.82 km). That's not only a January record: those are the highest values ever observed at those points outside of June, July, and August."



Figure 1. Monthly January sea ice extent for 1979 to 2011 shows a decline of 3.3% per decade. Image credit: National Snow and Ice Data Center.

The warm temperatures in Canada and record sea ice loss in the Arctic were also due, in part, to a strong negative phase of the Arctic Oscillation (AO). The Arctic Oscillation and its close cousin, the North Atlantic Oscillation (NAO) are naturally occurring pressure patterns in the Arctic and mid-latitudes. A negative AO and NAO results when we have weaker than normal low pressure over the Arctic, and weaker than normal high pressure over the Azores Islands. This fosters an easterly flow of air off the warm Atlantic Ocean into the Canadian Arctic, and also weakens the winds of the polar vortex, the ring of counter-clockwise spinning winds that encircles the Arctic. A weaker polar vortex allows cold air to spill southwards out of the Arctic into eastern North America and Western Europe. Thus, the strongly negative AO and NAO the past two winters have been largely responsible for the cold and snowy winters in these regions, and exceptionally warm conditions in the Arctic. I described this pattern in more detail in my December post titled, Florida shivers; Hot Arctic-Cold Continents pattern is back. It is possible that Arctic sea ice loss is largely responsible for the unusual Arctic Oscillation pattern we've observed during the past two winters, as well as for the record-strength ridges of high pressure observed over Greenland and Alaska this winter. It should not surprise us that Arctic sea ice loss would be capable of causing major perturbations to Earth's weather, since it is well known that changes from average in sea surface temperatures over large regions of the ocean modify the jet stream, storm tracks, and precipitation patterns. The El Niño and La Niña patterns are prime examples of this (though the area of oceans affected by these phenomena are much larger than what we're talking about in the Arctic.) Another example: Feudale and Shukla (2010) found that during the summer of 2003, exceptionally high sea surface temperatures of 4°C (7°F) above average over the Mediterranean Sea, combined with unusually warm SSTs in the northern portion of the North Atlantic Ocean near the Arctic, combined to shift the jet stream to the north over Western Europe and create the heat wave of 2003, the deadliest heat wave in history with 30,000 - 50,000 deaths in Europe.

References
Feudale, L., and J. Shukla (2010), "Influence of sea surface temperature on the European heat wave of 2003 summer. Part I: an observational study", Climate Dynamics DOI: 10.1007/s00382-010-0788-0


Figure 2. The 6-10 temperature forecast issued by NOAA's Climate Prediction Center calls for an above-average chance of warm temperatures across most of the U.S. by mid-February.

A warmer forecast for February
Over the past two weeks, the Arctic Oscillation has undergone a major transition, changing from negative to positive. This means that low pressure over the Arctic has intensified, which will act to speed up the counter-clockwise spinning winds (the polar vortex.) This spin-up of the polar vortex will tend to keep cold air bottled up the Arctic, leading to more Arctic sea ice formation and warmer winter conditions over the U.S. This warm-up is reflected in the latest 6 - 10 day temperature outlook from NOAA's Climate Prediction Center (Figure 2.) Could it be the groundhog was right, and we have only three more weeks of winter left? Time will tell--we have little skill predicting what may happen to the Arctic Oscillation more than about two weeks in advance.

Jeff Masters

Climate Change Sea Ice Winter Weather

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Renewed flooding in Sri Lanka kills 11, affects 1.05 million

By: JeffMasters, 10:21 GMT le 07 février 2011

Renewed flooding in Sri Lanka due to heavy monsoon rains has killed at least 11 people and inundated the homes of 1.05 million people over the past week. The floods occurred over the central, north, and east portions of the island, and have the potential to devastate the rice crop and cause hundreds of millions in damage. Many of the areas affected were also hard-hit by January's 100-year flood, which killed 43 people, affected over 1 million people, and did at least $500 million in damage. Those floods destroyed 21% of Sri Lanka's rice crop. Heavy rains from the annual northeastern monsoon are common in the region from December through February, but this year's rains have been enhanced by the strong La Niña event occurring in the Eastern Pacific. According to the United Nations, the rains in January in Sri Lanka were the heaviest in nearly 100 years of record keeping. The flood that resulted was a 1-in-100 year event, according to The U.N. Global Disaster Alert and Coordination System. Rainfall at Batticaloa, Sri Lanka, during the 42-day period December 1 - January 12 was 1606 mm (63"), which is about how much rain the station usually receives in an entire year (1651 mm, or 65".) Satellite estimates of rainfall over Sri Lanka for the first week of February show that up to 12 inches (300 mm) of rain has fallen. The latest rainfall forecast from the GFS model projects that a tropical disturbance (91B) near Sri Lanka will bring an additional 1 - 3 inches of rain to the flood area this week, so the flood waters will be slow to recede.


Figure 1. AP video of the latest flooding in Sri Lanka.

Jeff Masters

Flood

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Ice storm cripples Houston; Yasi the 2nd costliest Australian storm on record

By: JeffMasters, 16:13 GMT le 04 février 2011

A significant ice storm is in progress across southeast Texas, much of Louisiana, northern Mississippi, and southern Arkansas this morning, as the latest onslaught from the memorable winter of 2010 - 2011 continues. Houston, Texas recorded 1/10" - 1/4" inch of ice so far from the storm, resulting in a crippling of that city's transportation system. Numerous crashes have closed many area roads, and flights at local airports have been largely halted. Snowfalls of 1 - 3 inches will occur today along the northern edge of the ice storm region, in a swath from northeast Texas to western Kentucky. The storm will move into New England on Saturday, but will not bring heavy snow. The next chance for heavy snow occurs next Wednesday and Thursday, when the GFS model is predicting the formation of a winter storm capable of dropping a foot of snow in the Appalachians and inland areas of New England. However, it is too early to put much faith in this forecast.


Figure 1. Trees snapped off along the Chicago lakefront by winds from the Blizzard of 2011. Image credit: viewer uploaded photo from WGN.

Revisiting the Chicago blizzard
This week's blizzard in Chicago dropped 20.2" of snow on the city, Chicago's third-greatest snowstorm on record. But the tremendous winds that accompanied the blizzard--gusting to 61 mph at O'Hare Airport, and 70 mph at the Lakefront--made the storm Chicago's worst-ever blizzard as far as impacts on travel. Another remarkable feature of the storm were the intense thunderstorms that developed. According to an excellent write-up on the storm posted by the Chicago National Weather Service office, the Blizzard of 2011 had 63 lightning strikes, and several reports of hail. The most extraordinary hourly observation I've ever seen in a U.S. winter storm came at 9:51pm on February 1 at Chicago's Midway Field: A heavy thunderstorm with lightning, heavy snow, small hail or ice pellets, freezing fog, blowing snow, visibility 300 feet, a wind gust of 56 mph, and a temperature of 21°F. Welcome to the Midwest! Thanks go to meteorologist Steve Gregory for pointing this observation out to me.


Figure 2. Snow amounts from the February 1 - 3 blizzard of 2011 peaked at over 2 feet along the shore of Lake Michigan between Chicago and Milwaukee. Strong northeasterly winds pulled moist air off of the Lake in this region, allowing the "lake effect" to enhance the blizzard's snows in this region. Image credit: Chicago National Weather Service office.

Tropical Cyclone Yasi the second most damaging storm in Australia's history
Tropical Cyclone Yasi has dissipated, but the damage totals from the storm make it Australia's second most expensive tropical cyclone of all-time, according to Tropical Storm Risk, Inc. The storm's $3.5 billion price tag is second only to Cyclone Tracy, which hit Darwin on Christmas Day 1974, doing $3.6 billion in damage (2011 dollars.) Yasi roared inland over Queensland, Australia at 12:30am local time on Thursday as a strengthening Category 4 storm with 155 mph winds and a 930 mb central pressure. The cyclone missed the most populous cities on the coast, Cairns and Townsville, but damaged up to 90% of the buildings in the small towns near where the eye passed--Tully, Mission Beach, and Cardwell. A storm surge of 5.4 meters (17.7 feet) was observed at Cardwell, and there was substantial surge damage at the coast. Fortunately, the storm surge hit near low tide, resulting in a storm tide--the height of the water above land--of about 4.5 meters, more than 2 meters below what would have occurred had Yasi hit at high tide. Yasi moved quickly enough across Queensland after landfall so that major flooding was limited to just three locations near the coast. Yasi's central pressure of 930 mb at landfall made the storm the most intense recorded in Queensland since at least 1918, and possibly since 1899. In 1918, there were two cyclones (at Mackay and Innisfail) with measured pressures in the upper 920s/low 930s, but it is quite plausible that the minimum central pressures were lower than that. The 1899 (Mahina/Bathurst Bay) cyclone had a measured pressure (ship near shore) of 914 mb.


Figure 3. The tide gauge at Carwell, Australia during passage of Tropical Cyclone Yasi recorded a 5.4 meter (17.7') storm surge (red line). Since the surge came near low tide, the storm tide--the height of the surge above mean water--was only 4.5 meters (blue line). The storm tide would have been more than 2 meters higher had Yasi hit at high tide, and the damage from coastal flooding would have been huge. The green line shows the expected water levels at Cardwell due to the tide. Image credit: Queensland government.


Figure 4. Tropical Cyclone Yasi at 04:15 UTC February 3, 2011, as seen by NASA's Aqua satellite.

Jeff Masters

Winter Weather Hurricane

Updated: 22:21 GMT le 05 février 2011

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Nation digs out from massive blizzard; Cyclone Yasi rips through Australia

By: JeffMasters, 14:05 GMT le 03 février 2011

Chicago's third worst snowstorm on record is history, leaving in its wake a remarkable 20.2” of snow, snowdrifts up to ten feet high, and frigid below zero temperatures. Only the January 2 - 4 1999 blizzard (21.6") and January 2 – 4, 1967 blizzard (23”) dumped more snow on Chicago. The Groundhog's Day blizzard of 2011 had stronger winds than either of Chicago's other two record snowstorms, and thus was probably the worst snowstorm ever to affect the city, as far as impacts on travel go. Winds gusted as high as 61 mph at Chicago's O'Hare Airport, and winds at the Chicago buoy, 10 miles offshore in Lake Michigan, reached sustained speeds of 54 mph, gusting to 66 mph. Fortunately, Lake Michigan had so much ice on it that crashing waves were unable to cause significant flooding along the lake shore.

Chicago's 10 biggest Snowstorms:

1. 23.0 inches Jan 26-27, 1967
2. 21.6 inches Jan 1-3, 1999
3. 20.2 inches Feb 1-2, 2011
4. 19.2 inches Mar 25-26, 1930
5. 18.8 inches Jan 13-14, 1979
6. 16.2 inches Mar 7-8, 1931
7. 15.0 inches Dec 17-20, 1929
8. 14.9 inches Jan 30, 1939
9. 14.9 inches Jan 6-7, 1918
10. 14.3 inches Mar 25-26, 1970


Figure 1. A bus jack knifed on Lake Shore Drive in downtown Chicago on the night of February 1, 2011 during intense blizzard conditions, resulting in a dangerous situation where hundreds of cars became stranded behind the bus. Image credit: Viewer uploaded photo from WGN.

The most remarkable feature of this storm was its sheer size. Twenty-two states received snows of five inches or more, and over 100 million Americans experienced snow or freezing rain. Antioch, Illinois recorded the most snow of any location in the U.S., 27 inches. Also hard-hit were Missouri, Oklahoma, Wisconsin, Iowa, Indiana, and Vermont, which all reported more than eighteen inches of snow. Seven states reported freezing rain that left 1/2” or more of ice accumulation, which resulted in power outages affecting hundreds of thousands of people.

The strength of the high pressure system behind the Groundhog's Day Blizzard of 2011 was also remarkable. Pressure readings in Montana at the height of the blizzard were well above 1050 mb, the type of high pressure only seen once every twenty years or so in the U.S. The difference in pressure between this high and the mighty blizzard drove a flood of cold air southwards out of Canada, creating the very high winds that shut down road travel over most of the Midwest during the height of the storm. The unusually strong push of cold air southwards has caused major problems in northern Texas, which is unused to multi-day periods of below-freezing temperatures. Many power plants were knocked off-line by the severe weather, and record electricity demand has overwhelmed the electrical system, resulting in widespread rotating blackouts. A rare Southeast Texas snowstorm is expected today, due to a new storm system moving eastwards across the state. Houston is expecting 1 – 3 inches of snow through Friday. All flights leaving Houston between 3pm today and noon Friday have been canceled, because the airports have no de-icing fluid.

Tropical Cyclone Yasi hits Queensland, Australia
Tropical Cyclone Yasi roared inland over Queensland, Australia at 12:30am local time on Thursday as a strengthening Category 4 storm with 155 mph winds and a 930 mb central pressure. The cyclone missed the most populous cities on the coast, Cairns and Townsville, which experienced wind gusts to about 60 mph. Undoubtedly, tremendous wind damage occurred in the small towns of Tully, Mission Beach, and Bingal Bay where the eye passed. A storm surge of 5 meters (16 feet) was observed at Cardwell, and 3 meters (10 feet) at Clump Point. Townsville received a 2.5 meter storm surge that damaged some sea walls. This was the highest storm surge observed since 1971 there.


Figure 2. Pressure readings from Clump Point on the Queensland, Australia coast during passage of Yasi bottomed out at 930 mb as the storm passed overhead. Image credit: Australian Bureau of Meteorology.

According to an email I received from Blair Trewin of the Australian Bureau of Meteorology, ”Yasi is almost certainly the most intense landfall in Queensland since at least 1918, and possibly since 1899. In 1918 there were two cyclones (at Mackay and Innisfail) with measured pressures in the upper 920s/low 930s but it is quite plausible that the minimum central pressures were lower than that. The 1899 (Mahina/Bathurst Bay) cyclone had a measured pressure (ship near shore) of 914 mb.” However, the number of major tropical cyclones along the Queensland coast has declined since the 1870s, according to recent paper by Callaghan and Power (2010). They found that ”the number of severe TCs making land-fall over eastern Australia declined from about 0.45 TCs/year in the early 1870s to about 0.17 TCs/year in recent times—a 62% decline. This decline can be partially explained by a weakening of the Walker Circulation, and a natural shift towards a more El Niño-dominated era. The extent to which global warming might be also be partially responsible for the decline in land-falls—if it is at all—is unknown.”

References
Callaghan, J. and S. Power, (2010): Variability and decline in the number of severe tropical cyclones making land-fall over eastern Australia since the late nineteenth century, Climate Dynamics. DOI: 10.1007/s00382-010-0883-2


Figure 3. Tropical Cyclone Yasi at 03:35 UTC February 2, 2011, as seen by NASA's Aqua satellite.

Jeff Masters

Winter Weather Hurricane

Updated: 21:32 GMT le 03 février 2011

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Groundhog's Day blizzard pounds U.S.; Category 4 Yasi hits Australia

By: JeffMasters, 15:50 GMT le 02 février 2011

The great Groundhog's Day Blizzard of 2011 continues to pound a huge swath of the U.S. with heavy snows, destructive freezing rain, and dangerously cold and windy conditions. Over 1/2” of ice has caused power outages in Indianapolis, and up to .9” of ice has hit Columbus, Ohio. Ice amounts in excess of 1/2” have also affected Illinois, Connecticut, New Jersey New York, and Pennsylvania. Blizzard conditions continue in Chicago, where heavy snows of up to two inches per hour in high winds have crippled the city's transportation system. As of 9am CST this morning, Chicago's O'Hare Airport had received 19.5” of snow, making it city's third greatest snowstorm on record. Only the January 2 - 4 1999 blizzard (21.6") and January 2 – 4, 1967 blizzard (23”) have dumped more snow on Chicago. Today's blizzard had stronger winds than Chicago's other two record snowstorms, and thus this storm is probably the worst snowstorm ever to affect the city, as far as impacts on travel go. Huge drifts in excess of 6 feet are common in the city, and residents are finding it difficult to leave their houses, much less travel on area roads. Winds last night at Chicago's Calumet Harbor were sustained at tropical storm force, 39 mph, with gusts to 51 mph, and high winds tore off part of a fiberboard roof panel behind home plate at Wrigley Field, home of the Chicago Cubs. The Chicago buoy, 10 miles offshore in Lake Michigan, had sustained winds of 54 mph, gusting to 66 mph, last night. Winds are slowly decreasing across Chicago, and the blizzard will be over by early afternoon.


Figure 1. Lake Shore Drive in downtown Chicago on the night of February 1, 2011. Image credit: Viewer uploaded photo from WGN.

According to the National Weather Service, since snow records began in 1886 in Chicago, there have been 43 winter storms that produced 10 inches or more of snow. A 10 inch snow occurs about once every 3 years. A 15 inch snow occurs only once about every 20 years. The closest back to back 10 inch
snows were March 25-26 and April 1-2, 1970 (6 days apart). The longest period of time without a 10 inch snow or greater was February 12, 1981 to January 1, 1999 (almost 18 years). The earliest 10 inch snow was November 25-26, 1895 and the latest 10 inch snow was April 1-2, 1970. The most recent 10 inch snow was January 9-10, 2009.

Chicago's 10 biggest Snowstorms:

1. 23.0 inches Jan 26-27, 1967
2. 21.6 inches Jan 1-3, 1999
3. 19.5 inches Feb 1-2, 2011
4. 19.2 inches Mar 25-26, 1930
5. 18.8 inches Jan 13-14, 1979
6. 16.2 inches Mar 7-8, 1931
7. 15.0 inches Dec 17-20, 1929
8. 14.9 inches Jan 30, 1939
9. 14.9 inches Jan 6-7, 1918
10. 14.3 inches Mar 25-26, 1970

The great storm's fury now turns to New England. Boston received 9.7” of snow as of 7am from the storm, and another 4 – 8” is on the way today. Heavy snows in excess of 6 inches are expected in a swath extending from central New York through Massachusetts, Vermont, New Hampshire, and Maine today. Up to 1/4” of ice is expected through New England along the southern edge of the heavy snow belt. Cities near the coast such as New York City and Philadelphia will receive mostly rain from the storm, though.

Some selected snowfall totals from the Groundhog's Day Blizzard of 2011, as of 9am EST:

Spring Grove, IL 20.8”
Miami, OK 20”
Jefferson City, MO 18.3”
S. Fort Scott, KS 18”
Tulsa, OK 15”
Schenectady, NY 9.6”
Boston, MA 9.7”
Detroit, MI 7.5”
Oklahoma City, OK 7”
West Hartford, CT 6.5”
Abilene, TX 6”
Cedar Rapids, IA 4.5”


Figure 2. Satellite image of the Groundhog's Day Blizzard of 2011, taken at 10am EST February 2. Image credit: NASA/GSFC.

Category 4 Tropical Cyclone Yasi hits Queensland, Australia
Tropical Cyclone Yasi roared inland over Queensland, Australia at 12:30am local time this morning as a strengthening Category 4 storm with 155 mph winds and a 930 mb central pressure. Yasi is incredibly strong, its winds falling just 5 mph short of Category 5 status. This makes the storm one of the top-ten strongest cyclones to hit Australia since accurate records began in 1970.

The Australian Bureau of Meteorology had this to say about Yasi in their advisory last night:

YASI IS A LARGE AND VERY POWERFUL TROPICAL CYCLONE AND POSES AN
EXTREMELY SERIOUS THREAT TO LIFE AND PROPERTY WITHIN THE WARNING AREA,
ESPECIALLY BETWEEN CAIRNS AND TOWNSVILLE.

THIS IMPACT IS LIKELY TO BE MORE LIFE THREATENING THAN ANY EXPERIENCED DURING RECENT GENERATIONS.


Figure 3. Tropical Cyclone Yasi at 03:35 UTC February 2, 2011, as seen by NASA's Aqua satellite.

On Wednesday morning at 9:30am local time, Yasi hit tiny Willis Island, where a minimum pressure of 938 mb and a peak wind gust of 115 mph was observed before Yasi cut communications and damaged the radar.

Queensland faces three major threats from Yasi. The cyclone will bring torrential rainfall to a region with saturated soils that saw record flooding earlier this month. The latest rainfall forecast from NOAA using satellite-based rainfall estimates shows 4 – 6” of rain falling along Yasi's track over the next 24 hours. The GFS model is predicting that a wide swath of Queensland will receive 5 - 10 inches of rain over the next week, due to the combined effects of Yasi and a moist flow of tropical air over the region. Fortunately, Yasi is moving with a rapid forward speed, about 21 mph, and is not expected to linger over Queensland after landfall. The heaviest rainfall will miss Queensland's most populated regions to the south that had the worst flooding problems earlier this month, including the Australia's third largest city, Brisbane.

Yasi brought highly destructive winds to a region of coast between the cities of Cairns (population 150,000) and Townsville (population 200,000). Strong building codes have been in place in Queensland since the 1960s, which will help reduce the damage amounts. The fact that Yasi's eyewall missed these two major cities is lucky, since the coast is less populous between the cities.

A dangerous storm surge in excess of ten feet likely occurred along the left front quadrant of the storm where it came ashore. The tidal was going out when the storm struck, and the inundation from the storm surge will be about 1 meter (3 feet) less than it would have been had the storm hit at high tide.

Yasi is larger and more dangerous than Cyclone Larry of 2006, which hit Queensland as a Category 4 storm with 135 mph winds. Larry killed one person and caused $872 million in damage (2011 U.S. dollars.) Yasi will bring heavy rains to a region with soils already saturated from record rains, and may become a billion-dollar cyclone.


Figure 4. Radar image of Tropical Cyclone Yasi at landfall in Queensland, Australia. Image credit: Australian Bureau of Meteorology.

Links to follow:

Live streaming video from Channel 9 in Cairns, Australia

A new look for wunderground
The Weather Underground was the first commercial weather company to set up an Internet web site, way back in 1995. In the sixteen years since, we've steadily expanded our content, but today—in honor of Groundhog's Day—we've launched our first major site re-design. The WunderPress blog has a introduction to the new site, including a slide show that explains the new layout. You can click through the demo by hitting the “>” button. The launch of the redesigned wunderground.com also features our unique forecasting technology, BestForecast. Utilizing Weather Underground's network of personal weather stations (the largest in the world), BestForecast provides the industry's most localized weather forecasts by producing a forecast for every place in the world that has an airport or personal weather station—over 19,000 locations worldwide. We also provide the latest National Weather Service forecast for each county in the U.S., so users can choose which forecast works best for them. Coming soon: verification statistics, so you can see exactly how well the forecasts are doing for your location. We realize that not everyone will be happy with the newly redesigned site, so we still offer the old design at classic.wunderground.com.

Jeff Masters

Winter Weather Hurricane

Updated: 16:00 GMT le 02 février 2011

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Great Blizzard pounding Chicago; extremely dangerous Cyclone Yasi nears Australia

By: JeffMasters, 01:31 GMT le 02 février 2011

The Great Groundhog's Day Blizzard of 2011 is wreaking havoc tonight from Texas to Michigan, and is poised to spread dangerous winter weather eastwards to New England during the day Wednesday. Four states have declared states of emergency—Oklahoma, Missouri, Illinois, and Kansas—and the National Guard has been called out in Illinois and Missouri. Up to 1/2” of ice has caused power outages in Indianapolis, and blizzard conditions have engulfed Chicago, where heavy snows of up to two inches per hour are falling in high winds. Winds tonight at Chicago's Calumet Harbor were tropical storm force, 39 mph, with gusts to 49 mph. Winds gusts of 60 mph were occurring at the Chicago buoy, 10 miles offshore in Lake Michigan.

The storm will probably be Chicago's biggest blizzard since January 2 - 4 1999, when a storm dumped 21.6" of snow. With tonight's snowstorm expected to have very unstable air aloft, "thundersnow" with snowfall rates of 4 inches/hour is possible, and there is a chance today's blizzard could rival Chicago's greatest snow storm of all time, the blizzard of January 26 - 27, 1967. That immense storm dumped 23 inches of snow on Chicago, stranding thousands of people and leaving an estimated 800 Chicago Transit Authority buses and 50,000 automobiles abandoned on the city streets and expressways. Twenty six Chicagoans died in the blizzard, mostly due to heart attacks from shoveling snow. Strong winds in Chicago today are expected to generate 14 - 18 feet waves on Lake Michigan, with occasional waves up to 25 feet. A significant coastal flooding event is possible for the city, with beach erosion and flooding along Lake Shore Drive. I'll have a full update on the great blizzard in the morning.


Figure 1. Satellite image of the Groundhog's Day Blizzard of 2011, taken at 8pm EST February 1. Image credit: NASA/GSFC.

Category 4 Tropical Cyclone Yasi nearing Queensland, Australia
Tropical Cyclone Yasi continues to intensify as it speeds westwards towards vulnerable Queensland, Australia. Yasi, now a Category 4 storm with 140 mph winds, is under light wind shear of 5 - 10 knots, and over record warm ocean waters of 29°C (84°C). Low wind shear, record warm sea surface temperatures, and favorable upper-level outflow should allow the cyclone to maintain Category 4 strength until landfall Wednesday evening (local time.)

The Austrailian Bureau of Meteorology had this to say about Yasi in their latest advisory:

YASI IS A LARGE AND VERY POWERFUL TROPICAL CYCLONE AND POSES AN
EXTREMELY SERIOUS THREAT TO LIFE AND PROPERTY WITHIN THE WARNING AREA,
ESPECIALLY BETWEEN CAIRNS AND TOWNSVILLE.

THIS IMPACT IS LIKELY TO BE MORE LIFE THREATENING THAN ANY EXPERIENCED DURING
RECENT GENERATIONS.

On Wednesday morning at 9:30am local time, Yasi hit tiny Willis Island, where a minimum pressure of 938 mb and a peak wind gust of 115 mph was observed before Yasi cut communications and damaged the radar.

Queensland faces three major threats from Yasi. The cyclone will bring torrential rainfall to a region with saturated soils that saw record flooding earlier this month. The latest rainfall rates in Yasi's eyewall as estimated by microwave satellite imagery are 20 mm (0.8") per hour. The GFS model is predicting that a wide swath of Queensland will receive 5 - 10 inches of rain over the next week, due to the combined effects of Yasi and a moist flow of tropical air over the region. Fortunately, Yasi is moving with a rapid forward speed, about 21 mph, and is not expected to linger over Queensland after landfall. The heaviest rainfall will miss Queenland's most populated regions to the south that had the worst flooding problems earlier this month, including the Australia's third largest city, Brisbane.

Yasi will bring highly destructive winds to a region of coast south of the city of Cairns (population 150,000.) Townsville (population 200,000) is farther from the expected landfall of the eyewall, and should see lesser winds. Strong building codes have been in place in Queensland since the 1960s, which will help reduce the damage amounts. The fact that Yasi's eyewall will miss these two major cities is lucky, since the coast is less populous between the two cities.

A dangerous storm surge in excess of ten feet can be expected along the left front quadrant of the storm where it comes ashore. The tidal range between low and high tide along the coast near Cairns will be about 2 meters (6 feet) during the evening of February 2. Yasi is expected to hit near midnight, halfway between low and high tide. Thus, the inundation from the storm surge will be about 1 meter (3 feet) less than it would have been had the storm hit at high tide.

Yasi is larger and more dangerous than Cyclone Larry of 2006, which hit Queensland as a Category 4 storm with 135 mph winds. Larry killed one person and caused $872 million in damage (2011 U.S. dollars.) Yasi will bring heavy rains to a region with soils already saturated from record rains, and may become a billion-dollar cyclone.


Figure 2. Tropical Cyclone Yasi as captured by the Willis Island radar, as the western eyewall of Yasi moved over the island. Image credit: Australian Bureau of Meteorology, and kindly grabbed for me by Margie Kieper.

Links to follow:

Live streaming video from Channel 9 in Cairns, Australia

Jeff Masters

Winter Weather Hurricane

Updated: 01:33 GMT le 02 février 2011

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Great Blizzard pounds Midwest; Australia braces for Category 4 Yasi

By: JeffMasters, 14:37 GMT le 01 février 2011

The Great Blizzard of February 1 - 2, 2011 is here. Oklahoma City is experiencing whiteout conditions, with heavy snow of 2 inches per hour being driven by ferocious winds of 36 mph, gusting to 46 mph. With a temperature of just 9°F, this is an extremely dangerous storm for the city, and all of Oklahoma has been placed under a state of emergency. Seven inches of snow had fallen in Oklahoma City as of 7am EST. Dangerous blizzard conditions extend from Oklahoma, through northwest Arkansas, southeast Kansas, and southern Missouri this morning, and blizzard conditions are expected to spread northeastward into eastern Iowa, southern Wisconsin, most of Illinois, southern Michigan, northern Indians, and northwest Ohio later today. Cold air is being driven southwards out of Canada by a high pressure system over Montana that is at near-record strength. Pressures at Glasgow, Montana this morning were 1054 mb, close to the all-time U.S. high pressure record of 1064 mb set in Montana in 1983. Copious moisture is streaming northwards from the Gulf of Mexico to fuel the blizzard, and snowfall amounts will likely approach two feet across portions of Iowa and Illinois today, making it one of the top-ten snowstorms in history for the region. The storm will probably be Chicago's biggest blizzard since January 2 - 4 1999, when a storm dumped 21.6" of snow. With today's snowstorm expected to have very unstable air aloft, "thundersnow" with snowfall rates of 4 inches/hour is possible, and there is a chance today's blizzard could rival Chicago's greatest snow storm of all time, the blizzard of January 26 - 27, 1967. That immense storm dumped 23 inches of snow on Chicago, stranding thousands of people and leaving an estimated 800 Chicago Transit Authority buses and 50,000 automobiles abandoned on the city streets and expressways. Twenty six Chicagoans died in the blizzard, mostly due to heart attacks from shoveling snow. Strong winds in Chicago today are expected to generate 14 - 18 feet waves on Lake Michigan, with occasional waves up to 25 feet. A significant coastal flooding event is possible for the city, with beach erosion and flooding along Lake Shore Drive.


Figure 1. Chicago's Calumet Expressway near 138th after the record blizzard of January 26 - 27, 1967. Image credit: NOAA Photo Library.

Many major cities will likely receive over 12 inches of snow from the Great Blizzard of February 2011, including Kansas City, St. Louis, Detroit, and Boston. Perhaps of greater concern is the potential for a major ice storm along a swath from Northwest Oklahoma to Massachusetts. Widespread freezing rain is expected to bring over 1/4" of ice to many major cities, including Indianapolis, Columbus, Cleveland, Pittsburgh, and New York City. Some regions could see up to an inch of ice, and widespread power outages due to toppled power lines are likely for millions of people. Damages exceeding $1 billions are possible from this ice storm. In addition, the storm's powerful cold front brought severe thunderstorms to eastern Texas this morning, and severe thunderstorms will affect Louisiana, Mississippi, and Alabama today as the cold front moves east. NOAA's Storm Prediction Center has placed the region under its "slight risk" threat area for severe weather today, and a few isolated tornadoes may develop this afternoon in some of the heaviest thunderstorms.


Figure 2. A world of white. I don't recall ever seeing such a large area of the U.S. covered by winter weather warnings.

Extremely dangerous Tropical Cyclone Yasi bears down on flooded Queensland, Australia
Tropical Cyclone Yasi continues to intensify as it speeds westwards towards vulnerable Queensland, Australia. Yasi, now a Category 4 storm with 140 mph winds, is under light wind shear of 5 - 10 knots, and over warm ocean waters of 29°C (84°C). The sea surface temperatures over the region of ocean Yasi is traversing (10S - 20S, 145E - 160E) were 1.2°C above average during December, the latest month we have data for from the UK Hadley Center. This is the highest value on record, going back to the early 1900s. Low wind shear and record warm sea surface temperatures will continue to affect Yasi for the next day, and the cyclone should be able to maintain Category 4 strength until landfall Wednesday evening (local time.)

Queensland faces three major threats from Yasi. The cyclone will bring torrential rainfall to a region with saturated soils that saw record flooding earlier this month. The latest rainfall rates in Yasi's eyewall as estimated by NASA's Tropical Rainfall Measuring Mission (TRMM) satellite are 20 mm (0.8") per hour. The GFS model is predicting that a wide swath of Queensland will receive 5 - 10 inches of rain over the next week, due to the combined effects of Yasi and a moist flow of tropical air over the region. Fortunately, Yasi is moving with a rapid forward speed, about 21 mph, and is not expected to linger over Queensland after landfall. The heaviest rainfall will miss Queenland's most populated regions to the south that had the worst flooding problems earlier this month, including the Australia's third largest city, Brisbane.

Yasi will bring highly destructive winds to a region of coast near the city of Cairns (population 150,000.) Townsville (population 200,000) is farther from the expected landfall of the eyewall, and should see lesser winds. Strong building codes have been in place in Queensland since the 1960s, which will help reduce the damage amounts.

A dangerous storm surge in excess of ten feet can be expected along the left front quadrant of the storm where it comes ashore. The critical thing will be when Yasi hits relative to the tidal cycle. The tidal range between low and high tide along the coast near Cairns will be about 2 meters (6 feet) during the evening of February 2. If Yasi hits at low tide, a 10-foot storm surge will only bring the water levels four feet above mean tide, but a strike at high tide would bring water levels a full ten feet above mean tide. High tide is at 9pm EST (local) time in Cairns on February 2.

Yasi is comparable to Cyclone Larry of 2006, which hit Queensland as a Category 4 storm with 135 mph winds. Larry killed one person and caused $872 million in damage (2011 U.S. dollars.) Yasi is a much larger storm than Larry, though, and will bring heavy rains to a region with soils already saturated from record rains. Yasi is likely to be a billion-dollar disaster for Australia.


Figure 3. Tropical Cyclone Yasi at midnight GMT on February 1, 2011. At the time, Yasi was a Category 3 storm with 115 mph winds. Image credit: NASA.

Jeff Masters

Winter Weather Hurricane

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About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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