Uninterrupted sunshine returns Thursday along with comfortable, late May-level temperatures. The dramatic turnaround in our weather has silenced most area air conditioners. Only a week ago, highs here flirted with 90°. Wednesday’s peak afternoon reading of 70° was 20° cooler and the lowest daytime high here since May 28—nearly three weeks ago. The month has produced temperature surpluses each day and has generated the longest string of consecutive above-normal days of any June since 1919, when 26 above normal days occurred back to back.
A cool day this time of year isn’t a novelty in Chicago or the Midwest. Each June since 1981 has observed at least one daytime high below 70°.
Nighttime lows dip to the low 50s away from Lake Michigan Thursday night and to the low and mid 40s across the North Woods regions of Wisconsin and Michigan.

For the first time in two weeks, Canada is the source of Chicago’s weather on Wednesday. It’s a change which has been driven by a sharp realignment in steering winds aloft. It brings to an end one of the most prolific sets of early season 80° days on record here. Only two other years in more than a century of weather records (1973, 1984) have the opening two weeks of June hosted 12 days with 80s. The month’s opening 14 days are running 8.4° above normal, enough to rank it among the top ten warmest Junes on the books here.
Nine days this month have already exceeded 85-degrees, a tally which wasn’t reached until August 2 last summer.
Summer’s official open is only seven days away. The new season arrives at 1:46 a.m. next Tuesday, June 21 at the point the sun’s most direct rays fall as far north of the equator as at any time of the year.

Downpours drenched Chica-go’s Indiana suburbs and sections of central Illinois Monday. The rainfall came in the wake of 1-3” rains in sections of downstate Indiana this past weekend as Tropical Storm Arlene’s remnants passed. But, the weather story was all too familiar in the city and much of the remainder of the metro area. Brief showers teased some sections, but when all was said and done, O’Hare had tallied just 0.02” Monday and only a few drops fell at Midway Airport. The potential for some overnight t-storms continued as Monday closed, but wide-coverage rainfall appeared unlikely.
Downed trees and powerlines littered sections of Springfield and Decatur late Monday in the wake of 42,000 ft. tall t-storms.
A reconnaissance aircraft heads to the Caribbean Tuesday to investigate a low pressure moving over mid 80° waters and into an area of limited wind shear—conditions favorable for tropical development.