Chicagoans shivered through the first BELOW NORMAL DAY in 2 weeks and the 2nd COLDEST DAY OF FEBRUARY with this day’s high of 26 (normal high for Feb 17 is 36—10-deg warmer).

Cold like this hits hard in a month which has posted a 5-deg surplus and in which 13 of the past 17 days have come in ABOVE NORMAL and a year to date which, despite a few sharp cold blasts have seen nearly 80% of days come in MILDER THAN NORMAL.

The good news heading into the coming weekend is TEMPS ARE TO BOUNCE BACK to the month’s dominant ABOVE NORMAL WAYS. 

Saturday will see a 15 to 20-deg increase over today as gusty SW winds import milder Pacific air amid a good deal of sunshine.

Sunday looks even milder with a high topping 50-deg a good bet. The Saturday/Sunday high temps are to come in 7 to 15-deg above normal—with highs more typical of mid and late March than mid February.

LONGER RANGE: Temps cool modestly Monday and Tuesday next week though both day’s average temps are to still come in more than 5-deg above normal. 

I’ve mentioned the pattern taking shape by the middle and end of next continuing into the week which follows. It’s one in which frigid arctic air takes up residence the length of the Lower 48 along and south of the Canadian border. At the same time, WARM TEMPS are to occur across the South. The huge north/south temp spread sets up a powerful jet stream which sweeps from west to east across the country and gives rise to the development of a huge late winter storm season in the Wed/Thu time frame. 

Chicago sits straddles the boundary between warm and cold air and is likely to get in on the storm’s expansive precipitation shield and its likely strong wind field from the ENE which will start to come into play here Tuesday night. 

—Just what form the precip takes when it arrive Wednesday will be interesting to monitor. The potential appears to be there for a wintry mix as it looks now—but critical details on the system’s structure remain to be worked out in the 4-5 days before it arrives. 

—Colder air is likely to lock in that system’s wake maintaining the same sort of active jet stream across the region. The implication is next week’s active pattern is likely to spill over into the following week. 

–This week is to end having produced an 8-deg temp surplus. That drops to a 2-degree surplus next week and to a 3-degree deficit the week after. 

TONIGHT: Clear and cold with winds picking up from the southwest late. Low 23—but mid to upper teens inland. Reading are likely to become steady or rise a bit toward morning.

SATURDAY: Sunshine mixes with some clouds—turning windy and noticeably milder. High 43—a reading17-degrees warmer than today and 7-deg above normal.

SATURDAY NIGHT: More cloudy than not, breezy and milder. Temps may remain above freezing over a good part of the Chicago area.  Low 36.

SUNDAY: Becoming partly sunny, windy and unseasonably midl. Some 35 mph wind gusts likely by afternoon. High 51—5-deg above normal.

MONDAY: Sun at the open—but clouding over during the day. Chance of some sprinkles or flurries at night. Not quite as mild—but still ABOVE NORMAL. High 41.

TUESDAY: Mixed sun gives way to afternoon clouds. High 41—but 30s lakeshore.

WEDNESDAY: Cloudy and windy with rain, snow or a possibly wintry mix developing. 30+mph wind gusts take hold. High 36.

THURSDAY: Morning rain tapers off. Less windy as the day proceeds. High 39.

FRIDAY: Mostly cloudy, blustery and colder. High 30.