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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@overwash12:

Flash floods, not overall flooding. Last week we had some torrential rainfalls in the PR/VI area that dropped 4+ inches in under an hour and the ground is fairly well saturated in some areas as a result. Currently (1730 hrs Atlantic Time) we are getting some heavy rain on St. Croix but it is in short bursts. Guts and low-lying areas my experience some temporary flooding or even flash floods in steeper areas. PR will be experiencing the same, but they have more steep mountains and real rivers to deal with the runoff. Should be fine for the most part.
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@overwash12:

Flash flooding. We're having some heavy rains as I type this and PR is getting the same or maybe a bit worse. Ground is fairly saturated from last week's torrential rains so things could get hairy but the storm picture doesn't look that bad just yet.
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Quoting RastaSteve:
Doc posting wrong info? Well it wouldn't be the first time.

Possibly not--though his record of fails absolutely pales in comparison to yours, you'd have to agree. ;-)
Member Since: 8 novembre 2009 Posts: 4 Comments: 13603
NEW BLOG
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Quoting tatoprweather:
Flood warnings were issued for eastern Puerto Rico this morning.
What kind of floods? Flash floods coming down the streams,or low lying land floods?
Member Since: 24 juin 2007 Posts: 0 Comments: 1479
Quoting FFtrombi:
Last vestiges of La Nina are fading away, 3.4 region now up to -0.18!

Things have been" oscillating " from El-Nino to La-Nina and back again with a notable degree of celerity the past couple of years. Sign of yet another climate altering event.?
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Post #449

About time you showed up.
Member Since: 14 mai 2011 Posts: 0 Comments: 29
Quoting USAprimeCreditPeggy:
"EPAC"

I still say that is what Grampa Simpson shouted in the movie.



Perhaps. I don't remember though.
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New England and Mid_Atlantic states are getting copious amounts of rain on already flooded areas. At least 10 states with flood watches...
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"EPAC"

I still say that is what Grampa Simpson shouted in the movie.

Member Since: 14 mai 2011 Posts: 0 Comments: 29
Last vestiges of La Nina are fading away, 3.4 region now up to -0.18!

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Flood warnings were issued for eastern Puerto Rico this morning.
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429. RitaEvac 10:02 AM EDT on May 17, 2011
Floods, droughts, tornados and wildfires

Means hurricanes to come


That is what you said yesterday. I'm still waiting.
Member Since: 14 mai 2011 Posts: 0 Comments: 29
The rains will come when the rains come.

You should copyright that one.

;-)

Member Since: 14 mai 2011 Posts: 0 Comments: 29
Quoting RitaEvac:
Not for me Rasta, no rain


Good Morning Bud! How are you today?
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Quoting Rainman32:
Coffee deprivation here too didn't even notice. The link is "good" just apparently the model there hasn't been run for awhile.. Your link isn't fairing any better for us either. got another? I'll have another cup of coffee.


No. LOL! Doc I was just playing by the way as sometimes when I wake up I post wrong things. Coffee works wonders. My granddad drinks it 24 7
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Quoting RastaSteve:


LOL! Doc posting wrong info? Well it wouldn't be the first time. Here is the correct link below! Come on Doc get a cup of coffee then post.

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/ namer/gfs/00/index_tpp_m_loop.shtml
Coffee deprivation here too didn't even notice. The link is "good" just apparently the model there hasn't been run for awhile.. Your link isn't fairing any better for us either. got another? I'll have another cup of coffee.
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439. j2008
Quoting CybrTeddy:
EPAC mischief..

Great glob of convection for something to form out of isnt it?
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438. mnsky
THank you! labels=1 labels=1 labels=1
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Not for me Rasta, no rain
Member Since: 14 juillet 2008 Posts: 1 Comments: 9648
Back to work.
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Quoting IKE:

Zero here:(


Your rain should come later next week. hopefully!
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Quoting IKE:

Zero here:(


Wrong info again posted. LOL. March 18 thru 25.
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Notice the moisture surge coming north from the Caribbean toward the middle to end of the run.
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Quoting Jax82:


Anyone else notice the runs are 18-Mar to 25-Mar from the link Dr. Masters posted? Just wondering if there is a current run that i'm not seeing.


Use this link for current

Link

You can also use their link to have it in google earth
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431. IKE

Quoting JeffMasters:


180 hour QPF from the GFS model:

http://ahlquist.met.fsu.edu/research/ensacc/

Jeff Masters
Zero here:(
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Quoting Jax82:


Anyone else notice the runs are 18-Mar to 25-Mar from the link Dr. Masters posted? Just wondering if there is a current run that i'm not seeing.


LOL! Doc posting wrong info? Well it wouldn't be the first time. Here is the correct link below! Come on Doc get a cup of coffee then post.

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/ namer/gfs/00/index_tpp_m_loop.shtml
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Floods, droughts, tornados and wildfires

Means hurricanes to come
Member Since: 14 juillet 2008 Posts: 1 Comments: 9648
428. Jax82
Quoting lhwhelk:
So south Texas will stay dry. I tried playing the All Stars rain dance out in my back yard on my laptop, but the grass is still crunching when I walk on it. Sigh.
I would LOVE to see just a teeny-tiny tropical storm come along.


Anyone else notice the runs are 18-Mar to 25-Mar from the link Dr. Masters posted? Just wondering if there is a current run that i'm not seeing.
Member Since: 2 septembre 2008 Posts: 1 Comments: 1261
Complete Update





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Quoting CybrTeddy:


Spread the wealth!! Florida & Texas needs rain!

Here, here! We had a tiny taste of it with the last front.
Feast or famine so far this year.
Floods, droughts, tornados and wildfires.
My friend in Stuttgart reports unseasonally warm temperatures there for April and May.
I wonder what this all means.
Have a great day everyone.
Live, Love, Laugh, Smile.
Sometimes less is more. :)
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EPAC mischief..
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anyone notice the eastern pacific??
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One of the hottest and driest Aprils on record in France has parched farmland and cut water reserves, stoking worries of a drought similar to that experienced in 1976 and fuelling concern harvests will suffer in the European Union's top grain producer.

No substantial rainfall is expected in the next two weeks, weather expert Michele Blanchard told Monday's press conference.

In an interview with Reuters Insider, Meteo France forecaster Michel Daloz said that temperatures would also rise sharply in the next week, boosting groundwater evaporation.

http://www.reuters.com/article/2011/05/16/us-fran ce-drought-idUSTRE74F3PR20110516
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Quoting JeffMasters:


180 hour QPF from the GFS model:

http://ahlquist.met.fsu.edu/research/ensacc/

Jeff Masters
So south Texas will stay dry. I tried playing the All Stars rain dance out in my back yard on my laptop, but the grass is still crunching when I walk on it. Sigh.
I would LOVE to see just a teeny-tiny tropical storm come along.
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Key West has been so so dry since march. we may have seen about 1.5 inches since then. Please someone send us some rain, even if you have to FedEx it!!!!!!!!!!
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France in crisis as drought deepens

http://www.reuters.com/article/2011/05/16/us-fran ce-drought-idUSTRE74F3PR20110516

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Quoting JeffMasters:


180 hour QPF from the GFS model:

http://ahlquist.met.fsu.edu/research/ensacc/

Jeff Masters
Thanks Jeff! looks like a nice period of precip for Northern California, uh but not really what we were looking for in North Florida!
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418. JeffMasters (Admin)
Quoting Jax82:


Well at least the temperature this morning was nice, upper 50s for me on the coast :) We just got rain on Saturday, i know, it spoiled us.


180 hour QPF from the GFS model:

http://ahlquist.met.fsu.edu/research/ensacc/

Jeff Masters
417. Jax82
Quoting aquak9:
5 day QPF? That's not very nice.

Is there a 10-day QPF? dare I hope for anything?


Well at least the temperature this morning was nice, upper 50s for me on the coast :) We just got rain on Saturday, i know, it spoiled us.
Member Since: 2 septembre 2008 Posts: 1 Comments: 1261
Copy this into your browser to see a picture of the hail . www.facebook.com/photo.php?fbid=217621814922972&se t =a.106137452738076.12031.100000254655421&type=1&th eater ">
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Good Morning we had a rare hail storm here in Belize on Sunday with 2 1/2 inch hail i had to miss it all as i was in another village I only saw hail once in Belize when i was like 5 years old.
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Quoting Tropicsweatherpr:
This is what I am dealing with this morning.



Spread the wealth!! Florida & Texas needs rain!
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413. IKE
Post deleted. Hard to edit on here.
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412. P451


24hr WV Imagery. Quite a blocking pattern persisting out in the Atlantic. Has been for about two weeks now.

QPF 5-Day still showing 6" of rain for my area here in SE NY. That's going to be on top of the 1.5" we've already gotten from these few downpours the last few days.

Seems like every rain shower is a downpour regardless of the radar's dbz returns. Very very moist.
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RastaSteve - as for WU being "inaccurate", its not so much a matter of inaccuracy, but more of an issue known as GIGO. Garbage In, Garbage Out. If the PWS stink, the data will stink. WU has the same data feed from airports as the NWS, so they have the same info.

Also, just an observation I know has been made by many, but you've been predicting and talking about "the rainy season" for a good month and a half now. The rains will come when the rains come.
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Good Morning.
The very low levels of Sahara Dust right now is pretty unusual for this time of year.
If we accept that dust is part of the recipe for T-Waves off Africa not being able to develop into potential T-Storms, then this is another bad sign for this coming season.

Note that Sahara Dust is NOT proven to be either a detriment or a encouragement to Storm development. Research continues...
But it does seem to me that Dust indicates dry air, and storms would be more likely to have a chance at development in dust-free environments.
This has been the observed norm in the past 5 years or so.
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This is what I am dealing with this morning.

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Anyways have a good day guys as I have to get back to work.
Member Since: 21 Mars 2011 Posts: 0 Comments: 885
Quoting IKE:

I just looked them up and posted what they said. It is what it is.


Well Wunderground is not accurate then maybe that's why I don't pay for a membership here as they have wrong info at times.
Member Since: 21 Mars 2011 Posts: 0 Comments: 885

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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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