Extreme Heat Warning and Flood Advisory Issued for St. Louis, Missouri
ST. LOUIS, Mo. — June 27, 2026 — Residents across the St. Louis metropolitan area are preparing for a dangerous stretch of weather as an Extreme Heat Warning takes effect while some locations continue to deal with flooding concerns following recent heavy rainfall.
Forecasters warn that the region will experience a prolonged period of oppressive heat beginning Sunday and lasting through much of next week. Heat index values are expected to climb as high as 110°F, creating life-threatening conditions for anyone spending extended time outdoors. At the same time, recent rounds of thunderstorms have left saturated ground and standing water in portions of the metro area, prompting flood advisories in flood-prone locations.
Extreme Heat Creates Dangerous Conditions
The National Weather Service warns that prolonged exposure to extreme heat can quickly lead to heat exhaustion or heat stroke. High humidity will make temperatures feel even hotter, reducing the body’s ability to cool itself.
Residents are urged to:
- Drink plenty of water throughout the day.
- Limit outdoor activities during the hottest afternoon hours.
- Wear lightweight, light-colored clothing.
- Never leave children or pets inside parked vehicles.
- Check on elderly neighbors and anyone without reliable air conditioning.
Those working outdoors should take frequent breaks in shaded or air-conditioned areas.
Flood Advisory Remains in Effect
Although dangerous heat will become the primary weather threat, localized flooding remains possible where heavy rain recently occurred. Water may cover roads, low-water crossings, drainage areas, and urban streets.
Drivers should remember:
- Never drive through flooded roadways.
- Turn Around, Don’t Drown.
- Stay alert for rapidly changing weather conditions if thunderstorms redevelop.
Looking Ahead
The combination of extreme heat and lingering moisture will create hazardous conditions across eastern Missouri and southwestern Illinois through much of the upcoming week. Residents should continue monitoring forecasts and weather alerts for updates, especially if additional thunderstorms develop.
Preparedness remains the best defense against both heat-related illnesses and flooding hazards.
Stay weather aware and have multiple ways to receive emergency alerts throughout the week.
