Early in the morning, a number of meteorologists in the department of atmospheric sciences were carefully studying various weather maps and data, trying to determine if a severe weather outbreak was a possibility. The batteries were charged, the cars were gased, and the outlook was favorable.
The primary concern was would the warm front, which was located in Missouri, push its way through central Illinois? Morning weather conditions were overcast and cool, but as the day wore on, temperatures warmed, dew points slowly climbed, and at 1:30 PM CDT that afternoon, the decision was made to drive to western Illinois and see what develops. And develop it did.
Thunderstorms began to explode throughout Iowa, Missouri and Illinois after 21Z, or 4:00 PM CDT. These storms would lead to more than 30 tornadoes in the state of Illinois that afternoon. This section briefly looks at some key weather maps which provide some insight in to why the severe weather outbreak occurred.