Chicago, Illinois – Thunderstorms and a sweeping cold front will bring a sudden jolt to summer across Illinois starting Wednesday, with a sharp drop in temperatures expected by Thursday and lasting through the weekend.
According to the National Weather Service in Chicago, afternoon storms will begin moving across the region Wednesday, with the potential for isolated downpours and lightning between 1 and 8 p.m. A strong northwest wind shift behind the front will drop daytime highs by nearly 20 degrees in some areas. By Thursday, highs across Chicago and the surrounding suburbs will struggle to reach the upper 60s.
In addition to the cooler temperatures, beachgoers should take note: a high swim risk is in effect Thursday for Lake Michigan beaches, especially on the north side of the city, due to dangerous wave conditions and strong currents. Wind gusts up to 30 mph are possible Friday, along with lingering morning showers.
Daytime temperatures are expected to remain in the mid-60s to low 70s through Sunday — more typical of mid-October than early September. Residents are urged to dress accordingly and be cautious near lakefront areas.
Additional advisories may be issued if conditions worsen or shift.
Five Day Forecast for Chicago, IL
- Wednesday: High 71–82°F, storms likely in afternoon/evening
- Thursday: High 65–71°F, high swim risk, breezy and cool
- Friday: High 63–72°F, windy with AM showers
- Saturday: High 64–71°F, partly sunny and cool
- Sunday: High 66–73°F, mostly sunny, seasonably cool
