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Texas floods kill 5

By: Dr. Jeff Masters, 3:59 PM GMT on May 26, 2007

Flash flooding triggered by heavy thunderstorm rains of up to seven inches in 24 hours claimed at least five lives in Texas Friday, and large portions of the state remain under flood warnings or flood watches today, as thunderstorms continue across the state. All of those killed were swept away in their vehicles, and police were still looking for a missing man who drove around a barricade blocking a swollen creek.

Figure 1. Precipitation for the 24 hours ending at 8am EDT Saturday May 26, 2007.

Drought last year, floods this year
As I discussed in a March blog last year, grass fires in drought-parched Texas killed seven people on March 12 in the Panhandle, four of them in a car crash on I-40 caused by thick smoke obscuring visibility. More than 1,000 square miles of Texas burned that day--an area about two-thirds the size of Rhode Island. It's amazing what a turnaround has occurred in the past year. Most of Texas and Oklahoma were under drought conditions that reached the extreme level last spring (Figure 2), but this year, the Texas/Oklahoma drought is gone (Figure 3), and instead has moved into the Southeastern U.S. We don't understand very well what causes these shifts in drought patterns, but they do seem to be linked to changes in large-scale sea surface temperature patterns in the Atlantic and Eastern Pacific, plus shifts in the jet stream pattern. Are the floods in Texas this year and drought last year partially due to global warming? Yes, they might be. Global warming theory predicts that both droughts and floods will grow more severe as the climate warms. Floods will increase, since a warmer atmosphere holds more water vapor that can then rain out into heavier floods. Scientists have already documented about a 5% increase in global atmospheric water vapor due to global warming, and this extra moisture is undoubtedly causing heavier rains and more flooding in some regions. Drought will increase in intensity due to global warming, thanks to the hotter temperatures drought-striken areas will receive when jet stream and sea surface temperature patterns conspire to keep rainfall from the drought area.

Figure 2. Drought map for March 7, 2006.

Figure 3. Drought map for May 22, 2007.

Jeff Masters

Climate Change Flood

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments


Anyone think this could turn into something and move E towrds fl?
Looks like the CMC is forcasting an end to the fires in GA Link
Posted By: StormW at 1:24 PM GMT on May 29, 2007.

Please visit my blog.

Thanks much!

P.S. where are you located?

I just read yor blog and left a comment. I'm in Tampa, Fl.
Yes, these blobs may be interesting...

Ok...come check out my blog on this caribbean development. I have some information along with a little summary on what's going on now with this "system" (lol) in the caribbean. Thanks.

1009. snotly
Does the current pattern match that of '93 when the midwest had floods. It looks similar.
91E is looking quite health this morning. Think we'll see a td soon?
Rain in June in So Cal?!?! GFS is has been dancing with the idea. This would be much needed rain as most areas are running 11-15 inches below average and unlike most of the countery summer storms are rare and very isolated.

Long term...(thursday night through monday)...the 06z runs of the
WRF and the GFS are not in great agreement with the position of the
approaching upper low...or with their moisture fields. The GFS is faster
with the center...showing it just S of pt Conception Friday morning...
while the WRF has it centered about 300 nm west-southwest of pt Conception. The
GFS also shows more in the way of moisture with this system than it has
on previous runs...with a fair amount of moisture...albeit mostly middle and
high level moisture across the area Friday into Sat. The WRF...slower with the
system keeps things totally dry through Friday afternoon. The GFS shows
the upper low drifting very slowly southeastward and weakening Friday through Sat...
with an upper high strengthening over northern California. For now...will
maintain the current forecast which keeps a fairly decent marine
influence across the area Thursday night through Sat...with plenty of
night/morning low clouds and fog in coastal and most valleys areas...and
little change in temperatures...generally a bit below normal west of the mountains
and above normal in the mountains and dsrts. After Sat...a strengthening
upper high over northern California is forecast to build southward...causing heights to rise
across the area. This should cause the marine layer to shrink in
depth...with less extensive low cloudiness and less inland
penetration. Expect some warming for sun and Monday...especially in the
valleys...mountains and dsrts.
Does the current pattern match that of '93 when the midwest had floods. It looks similar.

Here is some good information on the weather patterns in 1993; sounds like what is happening right now, if a bit more extreme (floods and heavy rain in the central U.S.; extreme drought and heatwaves in the Southeast). Also, tornadoes.

was that pic taken at Jennings?
an area of heavy convection is fast approaching the low pressure in the sw caribbean. this will give the disturbance some energy to get its act together every thing seems to be in place for slow devepment. low shear high sst. the area still needs watching.
I had to take a big gulp when NWS Melb. discussion yesterday mentioned the the long term models and forecasts were drying out for our area in Fl. Fornately looking at the latest vis it is looking like we finally might be gettin rain.
Afternoon all.

I was just looking at that sf. Interesting. Not sure if there is enough left to pull it together. Not to mention, I would think the further N it goes the closer it gets to the shear that will tear it apart...