Weather

Daily Weather Brief for 3 July 2026: Extreme Heat Warning in St. Louis

The National Weather Service has an Extreme Heat Warning in effect for St. Louis, with dangerous heat and additional thunderstorm chances affecting holiday planning.

By Elise Navarro · July 3, 2026
Email Reporter
Daily Weather Brief for 3 July 2026: Extreme Heat Warning in St. Louis
CGN News / Cook Global News Network / CGN Weather Brief / All Rights Reserved

ST. LOUIS | St. Louis remains under an Extreme Heat Warning as dangerous heat and storm chances shape Friday and Independence Day planning, according to the National Weather Service.

The National Weather Service point forecast for Saint Louis showed an Extreme Heat Warning in effect until 8 p.m. CDT Saturday. Conditions at St. Louis Lambert International Airport late Friday morning included a temperature of 91°F, a heat index of 102°F, humidity at 59% and southwest wind at 12 mph.

Today and tonight

The St. Louis forecast called for a high in the mid-90s Friday with a chance of thunderstorms. Tonight, the forecast called for a slight chance of thunderstorms early, then mostly clear conditions with a low around 77°F.

The official warning language says dangerous heat can increase the risk of heat-related illness, especially for people working outdoors, attending events, traveling, playing sports or spending extended time without air conditioning.

Independence Day outlook

The Independence Day forecast carried another chance of showers and thunderstorms, mainly after noon, with a high in the mid-90s and heat-index values that may remain dangerous. Outdoor events, fireworks setup, youth sports, lake travel and long drives should include extra water, shade breaks and a way to receive updated weather alerts.

What is confirmed

Confirmed: the National Weather Service has an Extreme Heat Warning in effect for St. Louis through Saturday evening. Confirmed: Friday is hot and humid, with storm chances in the forecast. CGN News is not treating this brief as a replacement for official alerts, local emergency instructions or real-time radar.

What to watch next

Watch for updated National Weather Service warnings, local emergency management guidance and radar trends before outdoor work, public events or holiday travel. If thunder is heard, move indoors or into a hard-topped vehicle.

Additional Reporting By: National Weather Service Saint Louis Forecast; National Weather Service St. Louis Office; NOAA; National Weather Service Heat Safety

What This Means

Readers should treat this as a heat-safety planning day. The active Extreme Heat Warning means outdoor work, sports, travel and holiday events need water, shade, cooling breaks and updated official weather information.

The next step is to check the latest National Weather Service forecast and alerts before travel, outdoor work, school activities or Independence Day events.

Advertisement
Advertisement
Sponsored placement