WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.

Tornadoes produced by a snowstorm

|
Dear Tom,
Has there even been a tornado produced by a snowstorm or when snow was on the ground?

Mike Callan  Lemont

Dear Mike,
It is common for tornadoes to develop on the warm side of storms that deliver heavy snow, but it would be extremely rare for a twister to develop on the cold, snowy portion. Recently, on Feb. 5, 2008, 64 twisters battered the South while heavy snow swept the central Midwest. Though twisters usually form in a warm, moist surface environment, there are always exceptions. Dr. Harold Brooks of the National Severe Storms Laboratory in Norman, Okla. tells of a twister at Altus, Okla., on Feb. 22, 1975, with temperatures near freezing. The F2 storm killed two and injured 12 as it ripped through a trailer park. Twisters have also occurred during warm-ups when pre-existing snowpacks have not melted.