Chilly air loosens its grip on the Chicago area Wednesday--the first stage of a dramatic multiday warm-up expected to carry area temperatures to the highest levels since early September. Tuesday's blustery 43 degree peak reading matches the normal high here on March 8. And while a chilly rain fell much of the day across Chicago, record snows walloped the upper Midwest--focusing on Michigan’s Upper Peninsula, where up to 21.2 inches of snow fell at Rockland near Houghton. Other Upper Peninsula totals included 19.1 inches at Sidnaw, 18 inches at Alberta and 10 inches at Twin Lakes.
By contrast, record-breaking heat headlined western and southern U.S. weather. The eastward expanding dome of unseasonably warm air, expected to bring Chicago the warmest weekend since early October, produced sizzling early-season highs of 107 degrees at Thermal, 101 at Riverside and 95 at Los Angeles--all in California--while Corpus Christi, Texas, topped out at 95.
Warm air holds more moisture than cool air and computer projections suggest the water content of the air over Chicago is to more than triple over the next five to six days. The atmosphere here is to hold an estimated 0.40 inches of evaporated water Wednesday--but by late Sunday, that amount is to surge to 1.40. Dew points, meteorologists’ preferred measure of atmospheric water content, are to surge to 60 degrees this weekend for the first time since Oct. 6. Increased dew points lend a warmer "feel" to the air.
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune
