The longest spell of warm weather in three week—including the warmest weekend to date in 2023—is getting underway.

Chicago’s high temp hit 70-degrees for the 9th time this year. We’re running way ahead of last year at this time when only four 70s were on the books. We’ve had four 80s so far in 2023—last year had recorded only one to date.

The warm weather taking hold is the first extended spell of elevated temps in nearly 3 weeks. Sixteen of the past 19 days have averaged at or below normal—so this warm-up will be noticeable.

And the warming has legs. Modeling suggests each of the coming 15 days is to produce temps which are above normal.

The coming weekend is to come in an eye-opening 21-deg warmer than last and is to blow past our previous warmest 2023 weekend which occurred back on April 7 & 8th. This weekend is to see daytime highs in the 70s—even flirting with 80 and it is to average 68-deg—–which is more than 16-deg warmer than the April 7-8 weekend more than a month ago.

Adding moisture to warm air adds to its warm feel—and nature will do that sending 60-deg dew points our way by late Saturday—continuing Sunday into Monday. Of course, with moisture levels rising, so too will the prospect of shower and t-storm clusters which may first arrive on the scene Saturday night, Sunday, Monday and Tuesday. But they appear likely to come and go with 30 to 50% coverage currently indicated.

Interesting side bar—while warming is coming, it’s been a rough several days across Upper Michigan earlier this week. The NWS Marquette, Michigan office notes that the 27″ which fell in a single day Monday at Herman, Michigan is the heaviest single day snow tally on record east of the Mississippi so late in the season. A combination of rain and snow in the UP has deposited water equivalent precipitation topping 7″ in some areas.

HERE’S THE LATEST THURSDAY CHICAGO METRO FORECAST (5/4/2023)

TONIGHT: Partly cloudy, milder. Low 51—some mid 40s cooler inland locations.

FRIDAY through SATURDAY: Partly cloudy and warmer. Humidity’s will increase later Saturday. Lake breezes may reduce afternoon temps—but in a relatively localized strip up and down the Lake Michigan shoreline. High Friday 77 (60s beaches). Low Friday night 57. High Saturday 76.

SATURDAY NIGHT AND SUNDAY: Cloudy spells—but with peeks of daytime sun–and warm with higher humidity’s. Some clusters of showers and t-storms impacting 40 to 50% of the metro area at some point during the period. Low Saturday night 61. High Sunday 81—but closer to 70 on area beaches with some haze, even some patchy fog possible lakeside areas.

MONDAY: Variably cloudy. Several showers and t-storms possible—40-50% coverage. Warm inland—but cooler breezes possible along Lake Michigan—particularly noticeable Tuesday. High Monday 75.

TUESDAY: Becoming partly cloudy—lake breezes. Tuesday’s high 72, but 60s lakeshore.

WEDNESDAY: Partly sunny, warmest inland. High 72.