An Infrared Look at the U.S.

From NASA's Hurricane Web Page:

An Infrared Look at the U.S. 
The National Weather Service is expecting a Severe Weather Outbreak Likely Over Portions Of The Central And Southern Plains
A significant severe weather outbreak is expected later this afternoon into tonight over a large portion of the Central and Southern Plains. The potential exists for long track tornadoes, very large hail, destructive straight line winds, and heavy rainfall. By Wednesday, the severe weather threat shifts east to the Mid South and South Central U.S.
This infrared image from the AIRS instrument aboard NASA's Aqua satellite shows very cold cloud top temperatures in Wyoming and western Nebraska. AIRS showed that cloud tops were as cold as -63F/-53C (purple), indicating powerful uplift. Those storms are moving east today.