Extreme Heat Warning for Northern, Central and Southern Cook Counties
This alert is no longer in effect.
NOAA issued it on September 3, 2026, 11 days ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).
Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.
An Extreme Heat Warning is in effect until 7 PM CDT today for Northern, Central and Southern Cook Counties with heat index values of 100 to 105 expected.
This weather record, quickly
- Record type
- Extreme Heat Warning
- Affected area
- Cook County, Illinois
- Issued
- September 3, 2026
- Issuing authority
- NWS Chicago IL
Heat notices are time-bound and location-specific. Confirm the current forecast and local public-health guidance before relying on this archived record.
Record status: historical. It was issued 11 days ago; use the issuing agency's live warning service for current conditions in Cook County, Illinois.
Alert Details
Extreme Heat Warning issued by NWS Chicago IL. Effective from 2026-09-03T01:08:00-05:00 until 2026-09-03T19:00:00-05:00.
Affected Areas
Northern Cook, Central Cook, and Southern Cook Counties.
What You Should Do
The prolonged magnitude of observed and anticipated heat will lead to hazardous conditions, particularly for the elderly and those with pre-existing health conditions. Residents of the city of Chicago can call 311 to request well being checks for elderly friends or family members, or for information on finding the nearest cooling center. Consider altering outdoor plans. If you must spend an extended time outdoors, wear lightweight and loose fitting clothing. Take action when you see symptoms of heat exhaustion and heat stroke.
Expected Conditions
Dangerously hot conditions with heat index values of 100 to 105 expected. This is the third day in a row with a forecast or observed maximum heat index over 100 degrees.
Timeline
In effect until 7 PM CDT this evening. A cold front possibly accompanied by thunderstorms will move inland from Lake Michigan this afternoon and evening leading to rapidly improving conditions.
Original source: NOAA Official Notice ↗
Related Weather Alerts
All Weather Alerts →Similar notices nationwide by length or severity timing 8
Two cross-category peer sets, both computed from Areazine's own archive: notices with a similar body length, and notices near the same severity and agency date. These are drawn from other categories, not the same-feed Related list above.
Similar body length
Nearest notices by article body length (1,170 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to September 3, 2026.
Frequently Asked Questions
What people usually ask about a notice like this one.