St. Louis is starting Tuesday clear, muggy and already 77 degrees, with a dew point in the low 70s and southwest winds blowing near 17 mph. The bigger problem arrives this afternoon, when temperatures climb toward 99 degrees and the heat index could reach 108.
The National Weather Service has an Extreme Heat Warning in effect through 8 p.m. Wednesday for the St. Louis area, with heat index values potentially reaching 111. Tuesday is expected to be the most dangerous day of this stretch, despite mostly sunny skies and only a small chance of rain.
Dangerous Heat Holds Through Wednesday
Tonight will offer little relief, with partly cloudy skies, a low around 79 and heat index values still as high as 106. Southwest winds near 8 mph will continue, but the overnight air will remain thick and uncomfortable.
Wednesday will again reach near 99 degrees, with the heat index approaching 110. A slight chance of showers and thunderstorms arrives late Wednesday afternoon, and storms in the broader region could bring damaging wind or isolated hail, with the strongest severe-weather concern farther east across Illinois.
Storm Chances Rise Before A Weekend Rebound
Rain chances increase Thursday and Friday as a front moves through, with scattered showers and thunderstorms possible and highs easing to around 96 and 94 degrees. That break may be brief: mostly sunny, near-100-degree heat returns Saturday and Sunday before a more noticeable cooldown arrives Monday, when the high is forecast near 88.
Take The Heat Warning Seriously
Residents should drink plenty of water, limit strenuous outdoor activity during the afternoon and use air conditioning or another cool indoor space when possible. The City of St. Louis maintains cooling-center information, while the United Way of Greater St. Louis can provide cooling-center and energy-assistance details at 800-427-4626 or 2-1-1 from a landline.
Children and pets should never be left in vehicles, even for a short errand. Anyone showing signs of heat stroke should be moved to a cool place immediately, and 911 should be called.
