Dear Tom,
We have all heard “cooler near the lake.” How about “warmer near the lake”? What has to happen for that to occur?
Charles Poole, Ottawa, Ill.
Dear Charles,
When there is no lake breeze, “warmer near the lake” is actually a frequently occurring summer event here, although it is more accurate to describe the phenomenon as “warmer in the city.”
Metropolitan Chicago contains a “heat island” in the sense that the central, densely urbanized portion of the city area experiences higher temperatures, day and night, than surrounding rural areas. That’s because, by day, “city materials” like concrete, effectively convert the energy of sunlight into heat, releasing some into the air and storing the rest. At night, the city invariably remains warmer because its stored heat is radiated back into the air.
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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.)
