Chicago wakes up to a sticky start this morning, with clear skies, temperatures hovering near 66°F and humidity sitting in the low 80s. Mostly sunny skies are on tap, with a slight chance of showers or thunderstorms after 3 p.m. Highs should reach around 76°F, and an easterly breeze could gust up to 25 mph. Tonight looks partly cloudy and breezy, but the calm will not last long, because a multi-day heat event is lining up for Monday.
Dangerous Heat From Monday Through Wednesday
Forecasters expect temperatures to rocket into the mid to upper 90s Monday, Tuesday and Wednesday, with heat index values topping 100°F and possibly pushing 103 to 105°F inland. The National Weather Service has issued an Extreme Heat Watch for Cook County from Monday, June 29, 2026, at 12:00 p.m. through Wednesday, July 1, 2026, at 10:00 p.m., and Heat Advisories are slated for surrounding counties. Check NWS Chicago for the latest details.
Overnight temperatures will not offer much relief in dense neighborhoods near the lake, which means heat-related illness becomes a real concern as the holiday week ramps up. This is the kind of stretch where the pavement seems to radiate right back at you, so planning ahead is not optional.
Afternoon Showers Possible Today, Winds Picking Up
There is a slight, around 20 percent, chance of showers or a thunderstorm this afternoon. Any storms that form should be brief with only light additional rainfall, but they could kick up gusty winds in the 25 to 30 mph range. East to southeast winds will strengthen late today and turn more southerly into Monday, setting the stage for some hot, gusty afternoons.
If you have patio furniture, grills or other loose items outside, it is a good idea to secure them before the wind really gets going. Travelers should also pad in a little extra time later today in case a stray storm drifts across the commute.
Where To Find Relief
For anyone who needs air conditioned relief, the city and Park District maintain lists of cooling centers, libraries and pools that open during periods of extreme heat. Hours can change quickly, so call ahead or dial 311 before you head out. Cook County and the City of Chicago plan to activate staffed cooling options during the hottest days, and residents are urged to verify locations and hours before going.
See the official cooling center directory for addresses and contact information at the City of Chicago.
Heat Safety Tips
To stay safe, drink water frequently, even if you do not feel very thirsty, and avoid strenuous activity during the afternoon peak from roughly noon to 6 p.m. Check in on older neighbors, infants and anyone who does not have reliable air conditioning.
Never leave children or pets in parked cars, even for a short time, and use cool showers or damp cloths to help bring body temperature down if needed. Employers and outdoor workers should follow rest and shade protocols, shifting the heaviest tasks to the cooler parts of the day whenever possible.
