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Tornadoes, floods, and fires assault the nation

By: Dr. Jeff Masters, 2:43 PM GMT on April 26, 2011

A 1/2 mile-wide tornado smashed through Vilonia, Arkansas last night, killing four and destroying 50 - 80 houses. Vilonia is a small town of 3,800 north of Little Rock. The storm system responsible produced 38 suspected tornadoes yesterday, and also dumped 10 - 15 inches of rain over portions of Arkansas and southern Missouri. Flash flooding from the heavy rains killed four people in Arkansas last night. The heavy rains have also resulted in overtopping of the Black River levee near Poplar Bluff, Missouri, and over 500 homes have been evacuated in the town due to fears that the levee might fail. Poplar Bluff has received 12.86" of rain over the past three days, as of 11am EDT this morning. The greatest rain gauge-measured precipitation from the storm occurred in Springdale, Arkansas, where 17.09" inches has fallen.


Figure 1. Animation of a supercell thunderstorm 45 minutes after it produced the Viloni, Arkansas tornado at 7:25 pm CDT.


Figure 2. Radar-estimated precipitation from last night's storms.

Dangerous tornado outbreak expected today
Yesterday's tornado outbreak was merely a warm-up for today's onslaught, as NOAA's Storm Prediction Center has issued their highest level of severe weather potential, a "High Risk" forecast, for Northeast Texas and Southern Arkansas. This is just the second time this year that SPC has issued a "High Risk" forecast--the other was for the devastating North Carolina tornado outbreak of April 16, which generated 52 tornadoes that killed 26 people. Severe thunderstorms have already rumbled across Louisiana and Mississippi this morning, but today's main action is expected to erupt late this afternoon and early this evening in the "high risk" area. The tornado and severe weather outbreak will continue on Wednesday, when severe weather is expected to be concentrated in Tennessee and Kentucky, with a "moderate risk" of tornadoes. Preliminary tornado reports for the year 2011 show that this year is probably the busiest tornado season on record for this point in the season.


Figure 3. Severe weather threat for Tuesday, April 26, 2011.


Figure 4.
Chaser video of the Viloni, Arkansas tornado of April 25, 2011.

Extremely critical fire danger in Texas and New Mexico today
Spring storms commonly bring high winds to the Midwest this time of year, but today's storm will bring exceptionally high winds--and no precipitation--to the drought-stricken regions of West Texas and eastern New Mexico. As a result, an "extremely critical" fire weather day has been declared by the National Weather Service for the region, where high temperatures, low humidities, and powerful winds gusting to 60 mph will occur. The 24,000 acre Last Chance fire burning 33 miles southwest of Carlsbad, New Mexico near the Texas border is a particular concern, since it is currently 0% contained and is threatening many structures. This fire is expected to rage out of control today, thanks to humidities near 5%, temperatures in the low 90s, sustained winds near 40 mph, and gusts to 60 mph.


Figure 5. Fire weather forecast for today from NOAA's Storm Prediction Center.

2011 sets record for most acreage burned for April
According to the Interagency Fire Center, wildfires in 2011 have already burned nearly 2.3 million acres in the U.S. This is the greatest acreage on record so early in the year, and is more area than burned all of last year. The largest U.S. acreage to burn since 1960 was the 9.9 million acres that burned in 2007, so we area already 25% of the way to the all-time record fire year--with summer still more than a month away. Last night, a line of thunderstorms brought heavy rains of 2 - 3 inches from Dallas southeastwards through Louisiana, providing precious rains to a portion of Texas that was under their worst drought since 1925. However, the portion of Texas that has seen the worst wildfires (the black spots in the image below), received no rain.


Figure 6. Perimeters of the major wildfires in Texas during 2011 as of April 25. Image credit: GEOMAC Wildland Fire Support.

For those who want to lend a helping hand to those impacted by the widespread destruction this month's severe weather has brought, stop by the portlight.org blog.

Jeff Masters
Lambert St. Louis Tornado Damage
Lambert St. Louis Tornado Damage
Taken after the good friday tornado at Lambert Field St.Louis, MO
Super fat rainbow!
Super fat rainbow!
I watched as an anvil formed and as it apprached my house, it rained a bit and passed over, I thought to myself, that looks like there will be a rainbow with it, and voila!

Flood Tornado

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