CHICAGO — Periods of light rain are to fall amid SLOWLY RISING TEMPS overnight with the highest readings coming around midnight and approaching 50-degrees.

But the “WARMTH” WON’T LAST. The current storm system has powerful and cold backside winds swing down its west such and around its southern flank—AND THAT COLDER AIR IS TO HIT in Friday’s predawn with temps crashing from 50 at midnight to 35 as the day begins Friday.

Precipitation ends Friday–BUT POWERFUL WINDS, GUSTING TO 40 MPH WILL ARE TO SWEEP A COLD LATE SEASON AIR MASS into the area with daytime temps holding nearly steady before settling to the upper 20s toward nightfall.

AND THAT TAKES US INTO THE COLDEST CHICAGO WEEKEND SINCE LATE JANUARY AND THE 2ND COLDEST WEEKEND OF 2023 with JANUARY-LEVEL TEMPS despite the fact we’re past mid-March.

BY SATURDAY MORNING, thermometer readings will have plummeted to the mid teens—but with strong winds continuing through Saturday, Saturday morning winds chills will drop into the 2-below to 5-above range—incredibly cold for so late in the season.

While mixed sun will break from the clouds Friday amid the cold and wind, the storm system’s backwash clouds will sweep in with the potential for sporadic snow flurries and only passing peeks of sun Saturday.

SATURDAY’s daytime highs are likely to stay in the 20s—the first time that’s happened in more than 2 weeks—since a 29-deg high Feb 24th.

SUNSHINE emerges Sunday—but it won’t help temps much. Highs will fall WELL BELOW THE MID TO UPPER 40S which are normal—only reaching 37-deg.

AN ACTIVE WEATHER PATTERN CONTINUES NEXT WEEK with another ATMOSPHERIC RIVER STORM sweeping in with rain Wednesday into Wed night and a temporary boost in temps. Readings may actually ride to within striking distance of 50-deg –potentially even getting into the 50s by Thursday and Friday—but a new shot of modestly below normal air take hold by the following weekend well into the week which follows.

HERE’S MY LATEST THURSDAY CHICAGO METRO FORECAST

TONIGHT: Windy and rainy at times. Temps rise to 50 toward midnight—but sharp cooling after a windshift to the west in the predawn hours sends temps plummeting to A LOW OF 35 by morning with precipitation ending before daybreak after possibly mixing briefly with some snow.

FRIDAY: Quite windy and markedly colder with breaks in the clouds allowing mixed sunshine to emerge. Wind gusts to 40 mph at times. High 35—but holding steady then falling slowly to the upper 20s by dark.

FRIDAY NIGHT: Clouds return, windy and much colder. Passing flurries possible. Lows drop by morning to 15 with wind chills by daybreak from 2-below to 5-above Saturday morning.

SATURDAY: A good deal of cloudiness, windy and unseasonably cold. Passing flurries possible. High 28—a January-level temp nearly 20-deg below normal.

SUNDAY: Mostly sunny, breezy and, though not quite as cold–STILL WELL BELOW NORMAL. High 37 (Normal highs are in the upper 40s,

MONDAY: Sunshine followed by increasing cloudiness. More seasonable temps by afternoon. High 45.

TUESDAY: Mostly cloudy. Chance of sprinkles. High 49—but upper 30s or low 40s lakeshore.

WEDNESDAY: Cloudy and windy. Good chance of rain developing. High 48—but low 40s lakeshore.

THURSDAY: Rainy, windy and mild. High 54—lower lakeshore.

UPPER MIDWEST IN LINE FOR MORE SNOW OUT OF THIS STORM

The Saturday flurries offer just a taste of the wintry snows expected to sweep the upper Midwest with this storm. Sections of Upper Michigan and far northern Wisconsin, where snowfall will be lake enhanced and fall well into Saturday, are to see snowfalls of a foot to as much as 2 feet in favored areas downwind of Lake Superior. This comes on top a generous snow pack which sits 40″ deep in Bayfield, WI and 34″ in the Marquette and Munising areas of the Upper Peninsula.

THE LONGER PATTERN LOOKING AHEAD TO NEXT WEEK AND THE WEEK WHICH FOLLOWS REMAINS AN ACTIVE ONE WITH ANOTHER ATMOSPHERIC RIVER STORM TO RETURN RAINS WHILE BOOSTING TEMPERATURES TEMPORARILY WEDNESDAY INTO THURSDAY NIGHT NEXT WEEK

The temp increase will be a temporary one with readings settling to levels modestly below normal again by the following weekend and into the week which follows.