textproduct: Chicago

KEY MESSAGES

- After a dry and cooler day on Friday, there is another threat for severe weather late Saturday.

DISCUSSION

Issued at 242 PM CDT Thu Jun 11 2026

Broad mid and upper-level cyclonic flow will persist across the northern United States through the period. While this will maintain periodic opportunities for showers and thunderstorms into next week, we will experience a brief break in pattern for Friday. On Friday, a much less humid airmass shifting overhead on westerly winds in the wake of this evenings cold frontal passage will support a more comfortable weather day with temperatures topping out around 80 under mainly sunny skies.

Humidity values will be back on the increase again for Saturday as the low-level flow turns south-southwesterly in advance of the next approaching surface cold front dropping southward from the Upper Midwest. As the front shifts into our area late Saturday into Saturday night, a narrow corridor of slightly better low-level moisture return preceding it may support the development of some scattered showers and thunderstorms. Should these materialize, we will also have to monitor the potential for some more organized storms into Saturday evening, particularly given the presence of strong deep layer flow. While not looking to be a major severe weather event at this time, we certainly cannot rule out the threat for a few stronger storms to become capable of producing instances of damaging winds and hail. Accordingly, the SPC Day 3 outlook continues to highlight our area in a level 1 of 5 severe weather threat for late Saturday.

A push of much cooler and dry weather is anticipated for the second half of the weekend into early next week following the cold frontal passage Saturday night. Interestingly, this airmass looks to hold daytime highs in the 70s (lows in the low to mid 50s) early next week. Conditions then look to turn more active again (return of showers and thunderstorms) mid to late next week as an enhanced northwesterly upper-level flow pattern sets up across the central part of the country.

KJB

AVIATION /06Z TAFS THROUGH 12Z SATURDAY/

Issued at 1224 AM CDT Fri Jun 12 2026

Primary forecast concern this period is gusty westerly winds later this morning through sunset this evening.

Westerly winds will continue through sunset with speeds expected to diminish under 10kt early this morning and then increase again after sunrise with gusts into the lower/mid 20kt range from late morning through sunset. Winds will turn more to the southwest this evening with speeds diminishing under 10kt.

Some few/sct mvfr level clouds are possible early this morning along with some cu later this afternoon and then some mid level clouds Friday night into Saturday morning. cms

LOT WATCHES/WARNINGS/ADVISORIES

IL...None. IN...None. LM...Small Craft Advisory until 1 AM CDT early this morning for the IL and IN nearshore waters.