Overnight showers and thunderstorms associated with a passing cold front will move east this morning. Indications were that welcome rainfall totals in the 0.25 to 0.75" range occurred with greatest amounts on the north side of the metro area. During the week ahead, the jet stream should hold a west-east flow over the Great Lakes and with only minor diversions south, cold air should continue to hold well north of the U.S.-Canadian border. As a result, temperatures this week are expected to see-saw from 5 to 10° above normal to as much as 20° above normal. Triggering these fluctuations will be cold fronts again Wednesday and this coming weekend. Southerly flow in advance of the fronts will pump temperatures well into the 60s midweek and again next weekend. The +100 m.p.h. jet stream will continue to direct a parade of fronts off the ocean into the pacific Northwest, resulting in heavy snows in the mountains and rain or a rain/snow mix in the valleys.
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
