A warming spell midweek, then cold returns

A strong north-south jet stream aloft continues to pour chilling air out of the Arctic
into the eastern half of the United States. This upper flow will shift east enough to
allow an intrusion of warmer air into the Midwest.
The southern extent of the snow cover extends from the Iowa-Missouri border through
Central Illinois into southern Indiana and then east to the Atlantic Coast. Sunlight
reflected off the white 32-degree surface works against any temperature increase. Thus, the warm
southwest flow into the Chicago area midweek will be over an expansive snowpack which
will inhibit its influence. Nevertheless, readings will reach well into the 30s on Wednesday
and Thursday. A cold front will sweep through the area Thursday night, and Chicago's
temperatures will plummet to zero by the weekend.
EVEN FLORIDA NOT EXEMPT FROM COLD
The chilling cold should push all the way into southern Florida midweek, with lows
Wednesday and Thursday mornings in the 20s across northern portions and the 30s in the central
and even southern portions of the peninsula.
--By Paul Dailey, WGN Weather Center Meteorologist