Thunderstorms, which towered up to ten miles into the atmosphere from west Texas north to South Dakota late Wednesday, unleashed dozens of twisters across sections of five states. It was one of the 2007 season’s most active outbreaks to date. The storms erupted along a meteorological feature familiar to Plains residents—the so-called dry line. It’s the demarcation between air sinking out of the Rockies (and drying in the process) and humid northbound Gulf air.
The presence of a steep vertical temperature decline and powerful, storm-spinning jet stream winds aloft set the stage for Wednesday’s violent weather.
As tornadoes raked the Plains, the same spring storm buried the Rockies under snow measured in feet from Utah north to Wyoming and Montana. Nearly 30” was down late Wednesday at Brian Head, Utah where the elevation is 9,700 ft.
--By Tom Skilling, WGN-TV Chief Meteorologist
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
