Monday’s 55-deg high—the young month of March’s 2^nd warmest daytime high—-is likely to be the last temp THAT MILD in the coming two weeks. Chicago is headed into a colder pattern—not BARBARICALLY SO—but colder than normal by early and mid March standards. 

While 27 of the past 30 days –that’s 90% of them—have averaged ABOVR NORMAL, tomorrow is predicted come out close to normal temp-wise—then EACH OF THE 13 days which followed is to post temp deficits.

Last week came in nearly 8-deg ABOVE NORMAL. By comparison, this week (the period Sunday through Saturday) is to average just 0.6-deg above normal. And Chicago’s average temp is to dip next week to levels approaching 7-degrees BELOW NORMAL. This is quite a change.

What’s more, the presence of an expansive and strong Canadian high pressure, draped across southern Canada and the entire northern tied of U.S. states will keep east to northeast winds blowing through the coming work week—intensified by what could be a wintry weather system in the Thu night/Friday time frame.  A tight pressure gradient on this mammoth high pressure’s south side is to produce elevated wind velocities here much of the week.

The northeast flow Tuesday appears likely to tap drier air which is likely to erode clouds here and lead to the reappearance of sunshine—despite the chill.  Monday saw just 36% of its possible sun in Chicago. A good deal of cloudiness is likely to stage a comeback Wednesday and Thursday. 

Modeling places us near that system’s rain/snow demarcation line with the Thu night/Friday system—but also suggests a modestly colder environment than the system which produced the rain which changed to snow across Chicago’s southern suburbs this past Friday afternoon and evening. Promises to be another of these tricky late snow season winter systems which will have to be monitored. 

To date, March’s opening 6 days are running 5.4-deg ABOVE NORMAL—with each day of the month having come in ABOVE NORMAL.  But that having been said, March 2023’s opening 6 days are running 2.2-deg colder than the same period a year ago. 

MONDAY NIGHT:  Cloudy, modestly colder. Clouds break from the north over a portion of the area by morning. Turning fairly windy with 25 to 30 mph gusts developing. Low 35.

TUESDAY: Clouds give way to more sunshine than Monday, breezy and colder. Highs 14-deg lower than Monday reaching 41—but chillier with 30s along Lake Michigan. 

TUESDAY NIGHT: Clouding over again, breezy and chilly. Low 30.

WEDNESDAY and THURSDAY: More cloudy than not, breezy and chilly. Highs Wednesday 40.  Thursday’s high 39—but a bit colder and in the 30s each day downtown and along Lake Michigan.

THURSDAY NIGHT AND FRIDAY: Growing prospects for snow and windy.  Wind gusts build to 30 mph Friday. A wintry can’t be ruled out southern sections.  Low Thursday night 29.  High Friday 36.

SATURDAY: Partly cloudy to cloudy, cold and fairly windy. High 32.

SUNDAY: Mostly cloudy. Chance of a few flurries. High 34.

MONDAY: Clouds and possible flurries give way to partial clearing. Continued cold and breezy. High 34.