At 10:30 a.m. on September 3, the National Weather Service announced that the extreme heat warning covering central and northern Cook County has been cancelled, while the advisory continues for southern Cook County. The decision arrives on the third consecutive day of dangerously high temperatures across the Chicago region.
The warning, which had been in effect for the entire day, was originally scheduled to remain until 7 p.m. As temperatures began to moderate in the central and northern parts of the county, officials determined the criteria for the extreme heat warning no longer applied there, prompting the cancellation.
Residents of central and northern Cook County had been urged to stay hydrated, limit outdoor exertion, and watch for signs of heat‑related illness while the warning was active. With the warning lifted, those specific advisories are being withdrawn, though the National Weather Service will keep monitoring conditions and can issue new guidance if temperatures rise again.
In contrast, conditions in southern Cook County still meet the thresholds for an extreme heat warning. The advisory will stay in force until its planned expiration at 7 p.m., and officials continue to advise people in that area to drink plenty of fluids, seek shade, and check on vulnerable neighbors.
The National Weather Service said it will maintain observation of temperatures throughout the evening and will provide updates should the heat situation change, keeping the public informed as the third day of extreme heat progresses.