Dear Tom,
What is the most snow that’s fallen with a barometer reading greater than 30.00″?
Brian Carpenter, Sugar Grove
Dear Brian,
It stands to reason that this city’s biggest snowstorms have occurred with the barometric pressure less than 30.00″ as intense low-pressure systems that bring us the snow pass to our south. However, when Chicago does get snow with a very high barometer, it is usually lake-effect snow, brought in by the northeast flow around a large cold arctic high-pressure system positioned over the upper Midwest. Such was the case on Dec. 19, 1973, when 5 to 12 inches of lake-effect snow fell across the metropolitan area while the barometric pressure averaged 30.30″. On Jan. 26, 1927, Chicago received 0.6″ of lake-effect snow with the barometer at a lofty 30.97″, just 0.01″ below the city’s all-time record high reading of 30.98″ on Feb. 16, 1989.
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Tom Skilling is chief meteorologist at WGN-TV. His forecasts can be seen Monday through Friday on WGN-TV News at noon and 9 p.m.
Write to: ASK TOM WHY, 2501 Bradley Pl., Chicago, IL 60618 or asktomwhy@wgntv.com (Mail volume precludes personal response.)
WGN-TV meteorologists Steve Kahn, Richard Koeneman and Paul Dailey plus weather producer Bill Snyder contribute to this page.
