Big warm-up followed by mid-week cool down
Strong southwesterly flow will push temperatures into the 80s over most of northeastern Illinois today. Monday could see a cold front move into southern Lake Michigan bringing a cooling NE wind and a chance of showers into the north side of Chicago to the Wisconsin border. However the remainder of the metro area to the south and west should again experience the SW winds and mid-80s temperatures. As the jet stream pattern changes from an west-east flow along the U S—Canadian border to a strong northwest-southeast flow over the western Great Lakes, low pressure will move out of the northern plains through Wisconsin into Lower Michigan Tuesday. Showers and thunderstorms should accompany the associated cold front with sharply colder temperatures on the heels of following northeast winds. Wednesday will be the coldest day this week with slowly moderating temperatures into next weekend.
--By Paul Dailey, WGN Weather Center Meteorologist