ST. LOUIS | An active Extreme Heat Warning is in effect for St. Louis City and St. Louis County. CGN News is publishing this alert because official National Weather Service alert data includes one or more CGN coverage areas: St. Louis City, Missouri and St. Louis County, Missouri.
What is active now
The primary active alert is Extreme Heat Warning with NWS severity listed as Severe, urgency listed as Expected and certainty listed as Likely.
The alert became effective 27 June 2026 at 2:15 PM EDT. The current listed expiration or ending time is 3 July 2026 at 1:00 AM EDT. Readers should rely on the latest county-specific National Weather Service alert before making safety decisions.
Current official alerts
Extreme Heat Warning: NWS lists the affected area as Madison; St. Clair; Monroe; St. Charles; St. Louis; St. Louis City; Jefferson. Current listed expiration or ending time: 3 July 2026 at 1:00 AM EDT.
Flood Advisory: NWS lists the affected area as Clinton, IL; Madison, IL; St. Louis City, MO. Current listed expiration or ending time: 27 June 2026 at 5:00 PM EDT.
Flood Advisory: NWS lists the affected area as Jefferson, MO; St. Louis, MO; St. Louis City, MO. Current listed expiration or ending time: 27 June 2026 at 4:15 PM EDT.
Flood Advisory: NWS lists the affected area as St. Charles, MO; St. Louis, MO. Current listed expiration or ending time: 27 June 2026 at 5:30 PM EDT.
Coverage area
This CGN alert covers St. Louis City, Missouri and St. Louis County, Missouri. Nearby communities may experience different conditions, and warnings can change quickly.
Safety
Limit strenuous outdoor activity, drink water, check on older adults and people without reliable cooling, and never leave children or pets in vehicles. Outdoor workers should use shade, rest breaks and hydration plans.
Official instruction
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and…
This alert should be updated if the National Weather Service issues, cancels, extends or replaces the active alert. Do not rely on this article alone for emergency decisions. Keep wireless emergency alerts enabled and monitor official NWS, NOAA, local emergency management and trusted local broadcast sources.
Additional Reporting By: National Weather Service; NOAA; National Weather Service St. Louis