Temps plummeted to late April levels today—even cooler on the Lake Michigan shoreline amid winds which have gusted as high a 36 to 44 mph up and down the western Lake Michigan shoreline—from Wisconsin into northeast Illinois.

Temps, which peaked at 86 Tuesday, were more than 20 degrees cooler at O’Hare today—only reaching 67. And along the Lake Michigan shoreline, temps have hovered around 50-deg as the day’s powerful, full fetch “NNE” winds traveled the length of chilly Lake Michigan into the Chicago area. Southern Lake Michigan water temps hover around 53 degrees—but are in the upper 40s mid-lake.

Waves at the Wilmette buoy came in at 8 ft. Wed afternoon and white caps were visible as far as the eye could see out over Lake Michigan Wednesday.

Normal lows this time of year are in the low 50s—so tonight’s mid 40s will come in 7 degrees below normal—and sub normal highs are predicted Thursday with highs likely to average a few degrees cooler than today.

But coming days will see the pressure gradient—and, therefore the winds—relax allow this air mass, trapped in place over the coming week thanks to a “blocking pattern” aloft—to begin warming.

And daytime highs way from Lake Michigan could be at or above 80 by Saturday afternoon—just in time for the Memorial Day weekend.

The warming is to add a few degrees to Chicago area high temps each day from Friday through mid next week when there are growing indications 90-deg temps look to be a good bet. An examination of Chicago high temps since 1942 show that 53% of those 81 years have produced a 90-deg temp by June 3—which appears to be what’s on tap this year.

The air is dry—dew points and relatively humidity’s are low and expected to remain that through the Memorial Day weekend so temps will cool at night and warm vigorously during the day. Also—lake breezes—in other words, easterly winds off Lake Michigan—are to be a daily occurrence into next week, so daytime highs will be cooler along Lake Michigan each day. But with a much lighter wind regime taking shape, the inland penetration of cool air will be limited. And even on area beaches, daytime highs in the 70s by Sunday and Monday should make for some wonderful holiday weekend beach weather.

But lake temps are still very cool. So hypothermia remains a risk and care should be taken swimming in the chilly water despite warm air temps.

And the rain situation remains dismal. May is headed for a close as Chicago’s second driest on the books and there appears little prospect for organized rainfall for the foreseeable future—which means into next week. There will be an increase in moisture levels Wednesday forward next week and that’s when scattered t-storms may “bubble up” across the area.


TONIGHT: More clouds later tonight—but until then partly cloudy, breezy and much cooler. Low 46.

THURSDAY: Morning cloudiness diminishes—turning sunny, breezy and cool for the season with late-April level temps around 10-deg below normal. High 64—but 50s beaches.

THURSDAY NIGHT: Clear, cool. Winds diminish. Low 46.

FRIDAY: Sunny with lighter winds and milder temps by afternoon. High 73—but low to mid 60s lakeshore.

SATURDAY: Generous sun mixes with some clouds in the afternoon. Warmer. High 81—but mid 60s to low 70s lakeshore and beaches.

SUNDAY & MEMORIAL DAY (MONDAY): A good deal of sunshine mixed with air weather clouds. Daytime warming continues, though cool at night. High Sunday 83. Monday’s high 88—but 70s each day on area beaches and near Lake Michigan.

TUESDAY: Partly sunny quite warm. High 90—but mid 70s immediate lakeshore.

WEDNESDAY: Mixed sun and clouds, hot, moderate humidities. Chance of an afternoon shower or t-storm. High 92.