Unprecented floods on the Mississippi, in Colombia, and Canada

By: Dr. Jeff Masters , 14:58 GMT le 16 mai 2011

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The great Mississippi River flood of 2011 continues to make history, with Saturday's opening of the flood gates of the Morganza Spillway marking just the second time that flood control structure has been used since its construction in 1956. With the Morganza, Bonnet Carre', and Birds Point-New Madrid Spillways all open, the Army Corps of Engineers has now opened all of its major spillways simultaneously for the first time ever. The Mississippi is rising at Vicksburg, Mississippi, where the water has now reached 56.5', exceeding the previous all-time record of 56.2', set during the great flood of 1927. Natchez, Mississippi, is also at its greatest flood height on record, with the water at 60.6'. The previous record high was 58', set in 1937. However, the opening of the Morganza spillway has reduced the predicted heights of the great flood of 2011 from Natchez to New Orleans by 1 to 1.5'. This will serve to greatly reduce the pressure on the levees and on the Old River Control Structure, which as I discussed in my previous post, is America's Achilles' heel, and must be protected. According the National Weather Service, flood heights along the Lower Mississippi from Natchez to New Orleans will peak this week, and slowly fall next week. Rainfall over the next five days is expected to be minimal over the Lower Mississippi watershed. The next chance for significant rain over the region will come Sunday, May 22.


Figure 1. Saturday's opening of the first gate on the Morganza Spillway, as seen on the live feed from USTREAM.

Devastating flooding continues in Colombia
Devastating flooding has hit South America in Colombia, where exceptionally heavy spring rains have killed at least 425 people so far this year, with 482 others missing. Damages are in the billions, and there are 3 million disaster victims. "Some parts of the country have been set back 15 to 20 years", said Plan’s Country Director in Colombia, Gabriela Bucher. "Over the past 10 months we have registered five or six times more rainfall than usual," said the director of Colombia's weather service, Ricardo Lozano. Up to 800 mm (about 32 inches) of rain has fallen along the Pacific coast of Colombia over the past two weeks (Figure 3). The severe spring flooding follows on the heels of the heaviest fall rains in Colombia's History. Weather records go back 42 year in Colombia. Colombia's president Juan Manuel Santos said, "the tragedy the country is going through has no precedents in our history." The 2010 floods killed 571 people--the second deadliest year for floods in Colombian history, next to 1987. The floods did over $1 billion in damage, and affected 2.8 million people. In many places, the flood waters from this great disaster never fully receded, and are now rising again due to this latest round of intense flooding. More rain is in the forecast--the latest forecast from the GFS model calls for an additional 5 - 10 inches (200 - 400 mm) across much of western and northern Colombia in the coming week.


Figure 2. Satellite-observed rainfall over Colombia during the past two weeks shows a region of up to 800 mm (about 32 inches) has fallen near the Pacific coast. Image credit: Navy Research Lab, Monterey.

Colombia's rainy season usually has two peaks: one the fall in October, then then another in the spring in April - May. The heavy rains are due to the presence of the Intertropical Convergence Zone, the area encircling the earth near the Equator where winds originating in the northern and southern hemispheres come together. When these great wind belts come together (or "converge", thus the name "Convergence Zone"), the converging air is forced upwards, since it has nowhere else to go. The rising air fuels strong thunderstorm updrafts, creating a band of very heavy storms capable of causing heavy flooding rains. In La Niña years, when a large region of colder than average water is off the Pacific coast of Colombia, rainfall tends to increase over Colombia. La Niña was moderate to strong during the fall 2010 rains and floods in Colombia, and was largely to blame for Colombia's deadly rainy season. However, in recent months, La Niña has waned. April sea surface temperatures off the Pacific coast of Colombia (0° - 10°N, 85° - 75°W), warmed to the 13th highest temperatures in the past 100 years, 0.68°C above average. Thus, this month's flooding in Colombia may not be due to La Niña.

See also my December 2010 post, Heaviest rains in Colombia's history trigger deadly landslide; 145 dead or missing


Figure 3. Dramatic video of flooding in Colombia over the weekend. Flood waters swept away cars and buses in a busy street in the city of Barranquilla, and passengers climbed on the roofs of their vehicles in order to escape the flood waters. Video credit: BBC.

300-year flood in Canada; wildfires destroy large portions of Slave Lake, Alberta
In Manitoba, Canada, heavy spring snow melt in combination with heavy rains have combined to create record flooding on the Assiniboine River. Authorities intentionally breached a levee over the weekend to save hundreds of homes, but inundated huge areas of farmland as a result. The flood is being called a 300-year flood, and damages are already in excess of $1 billion. In Alberta, Canada, reverse extreme is causing havoc: severe drought and strong spring winds have made ideal conditions for wildfires, which swept into the community of Slave Lake (population 6,700) yesterday. The fires destroyed hundreds of buildings, burning down the town hall and at least 30% of the town, according to preliminary media reports.


Figure 4. Video of the May 15, 2011 Slave Lake fire.

First tropical wave of the year over the Atlantic
The first tropical wave of 2011 is now over the tropical Atlantic near 6°N 46°W, according to the latest Atlantic Tropical Weather Discussion. The wave will bring heavy rain to the northeast coast of South America over the next two days, but is too far south to be a threat to develop into a tropical depression. The Atlantic hurricane season is just two weeks away, and the Eastern Pacific hurricane season began yesterday. So far, the models are not predicting any tropical storm development in the East Pacific or Atlantic over the next six days.

Jeff Masters

The Great Flood of 2011 (jperilloux)
KCS train crossing the trestle through the Bonnet Carre Spillway at Norco, LA. Flood water diverted from Miss. River
The Great Flood of 2011

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Oh Boy!
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lucky enough to travel through panama this week. this country has the canal and is becoming a power house. recession? not there. panama city looks like dubai central american style. happy weather
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Quoting sunlinepr:
Tragic Result Of Lost Lives



You can clearly see where the MJO and ITCZ lie.
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202. Jax82
Quoting sunlinepr:
Tragic Result Of Lost Lives


troll/trōl/
Noun: A mythical, cave-dwelling being depicted in folklore as either a giant or a dwarf, typically having a very ugly appearance. ;-)

haha and there is a wiki page for 'Trolls'
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201. MTWX
Well you know the tropical seasons are starting when the blog looks like this!!! Looks like opening Morganza is helping.. Hopefully everything goes well and the levees hold up!
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Beware of the.... Tragic Result Of Lost Lives

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Quoting RingOfDestruction:


You're Cody? Oh snap, I think I have you on Facebook, BRB, let me double check, just to make sure. Canes, how you've been, brah?


You definitely do not have me on facebook.
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Quoting TropicalAnalystwx13:


Hey...I'm doing good, how about you?


Can't complain honestly..... holdin' up here.
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Quoting USAprimeCreditPeggy:
caneswatch, you are the only person to get my handle.


I'm surprised, I thought a lot more would know about it.
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Quoting TropicalAnalystwx13:


Your wishing for thousands/millions of people to get killed? Seriously?!


I've wished many times that an EF-5 tornado would hit his house and his house only.
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194. Jax82
Ignore, no quoting, move on. Simple process for this season :)
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Quoting caneswatch:


Look who's back.... how are ya doin' Cody?

Don't mind the troll BTW.


Hey...I'm doing good, how about you?
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Quoting TropicalAnalystwx13:


Your wishing for thousands/millions of people to get killed? Seriously?!


Look who's back.... how are ya doin' Cody?

Don't mind the troll BTW.
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Quoting pottery:

ommmmmmmmmmmmm>>>>>>>>>


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I'll have a blog entry out in about 15-30 minutes, first of 2011.
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Quoting TropicalAnalystwx13:


yes, please.

ommmmmmmmmmmmm>>>>>>>>>
Member Since: 24 octobre 2005 Posts: 0 Comments: 24648
Quoting aquak9:
Let us pray...


yes, please.
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Let us pray...
Member Since: 13 août 2005 Posts: 171 Comments: 26253
Post 180, I concur.

Post 181, no, we are not happy.
Member Since: 14 mai 2011 Posts: 0 Comments: 29
Quoting USAprimeCreditPeggy:
Now we're cooking with gas!


Now that is your perfect Avatar
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hmmm...more like dodgeball preseason.
Member Since: 13 août 2005 Posts: 171 Comments: 26253
it's trolling pre-season.

Is that like baseball pre-season?
Member Since: 14 mai 2011 Posts: 0 Comments: 29
Quoting jeffs713:
172.

You need a lesson in trolling. Being so painfully obvious in your trolling kinda defeats the purpose. But then again... anyone trolling now is painfully obvious.
it's trolling pre-season.
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It has been warm today in San Juan and Mayaguez,Puerto Rico because of the southern winds,despite cloud cover and showers that have been falling.There is also some haze in the air as I can see a semigray sky.

PUERTO RICO/U.S. VIRGIN ISLANDS HOURLY WEATHER ROUNDUP
NATIONAL WEATHER SERVICE SAN JUAN PR
200 PM AST MON MAY 16 2011

PRZ001-004-161900-
PUERTO RICO

CITY SKY/WX TMP DP RH WIND PRES REMARKS

SAN JUAN LMM PTSUNNY 90 72 55 SE8 29.85F HX 96

MAYAGUEZ PTSUNNY 91 72 52 SW9 29.87 HX 98
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jeffs- it's kinda like having a fish on the hook, and just playin' with it for a while.
Member Since: 13 août 2005 Posts: 171 Comments: 26253
172.

You need a lesson in trolling. Being so painfully obvious in your trolling kinda defeats the purpose. But then again... anyone trolling now is painfully obvious.
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Oughtta let people in Lousiana and Texas Siphon that water in water tanks and use it on the drought
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Quoting USAprimeCreditPeggy:
With posts like that, RingofDestruction will be going down down down in a burning ring of fire before the day is through.


We can only hope.
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Don't think SAL will be a problem at all this season...

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Don't worry...it's just a fish flood....or maybe a spud flood.

Flood WarningFLOOD WARNING
IDC011-162201-
/O.CON.KPIH.FL.W.0003.000000T0000Z-000000T0000Z/
/SNAI1.2.RS.110510T2100Z.110519T0600Z.000000T0000 Z.NO/
101 PM MDT SUN MAY 15 2011

...FORECAST FLOODING INCREASED FROM MINOR TO MODERATE SEVERITY...
THE FLOOD WARNING CONTINUES FOR...
THE SNAKE RIVER AT BLACKFOOT.
* AT 12:15 PM SUNDAY THE STAGE WAS 10.4 FEET.
* FLOOD STAGE IS 10.0 FEET.
* MINOR FLOODING IS OCCURRING AND MODERATE FLOODING IS FORECAST.
* FORECAST...THE RIVER WILL CONTINUE RISING TO NEAR 11.1 FEET BY
EARLY THURSDAY MORNING. ADDITIONAL RISES MAY BE POSSIBLE
THEREAFTER.
* IMPACT...AT 11.0 FEET...LOWLAND FLOODING WILL OCCUR. FLOODING IS
POSSIBLE ALONG US HIGHWAY 26 BENEATH THE INTERSTATE 15 UNDERPASS.

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With posts like that, RingofDestruction will be going down down down in a burning ring of fire before the day is through.
Member Since: 14 mai 2011 Posts: 0 Comments: 29
Quoting MississippiWx:


I'll gladly trade with you...60s here for high and lows in the 40s...in MAY. Ugh...this is not MS weather. I am so tired of the cold...


That's like winter time here in SE TX, I was in Galveston yesterday at the San Luis pool and bar, women in string bikinis and people in the water sipping alcohol
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don't forget rabid
Member Since: 13 août 2005 Posts: 171 Comments: 26253
Quoting RitaEvac:
Look to see sunny skies with temps in the 80s all week long....back to you guys


I'll gladly trade with you...60s here for high and lows in the 40s...in MAY. Ugh...this is not MS weather. I am so tired of the cold...
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NWS says 74 °F, but I know that has to be false...More like 84 °F.
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Look to see sunny skies with temps in the 80s all week long....back to you guys
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Quoting TropicalAnalystwx13:
ahhh....the old Taz reporting posts, JFV, the chart....reminds of last season....good times XD.
lol
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Quoting TropicalAnalystwx13:
ahhh....the old Taz reporting posts, JFV, the chart....reminds of last season....good times XD.


And the season before last, and the season before that one, and so on and so forth...
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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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