Dear Tom,
Are tornado warnings ever issued for funnel clouds?
— Patricia Nesbit
Dear Patricia,
A meteorologist would not hesitate to issue a tornado warning based on the sighting of a funnel cloud if the report appeared to be reliable and could be associated with a reading from Doppler radar that shows a rotation in the clouds in the area.
A funnel cloud becomes a tornado when it hits the ground. During periods of severe weather, it could only be a matter of seconds before a funnel reaches the ground and starts causing damage.
Storm spotters and weather professionals often use the redundant phrase “tornado on the ground” to convey a sense of urgency and danger to the public about an approaching twister. The redundancy makes it clear that the storm is an actual tornado and poses an immediate threat.
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Write to: ASK TOM WHY, 2501 Bradley Pl., Chicago, IL 60618 or: asktomwhy@wgntv.com
Weather Report is prepared by the WGN-TV Weather Center, where Tom Skilling is chief meteorologist. His forecasts can be seen Monday through Friday on WGN News at noon, 5:55 p.m. and 9 p.m.
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