Wednesday morning, June 24, 2026, starts out clear and cool in St. Louis, around 63°F with muggy dewpoints hanging in the air. Through the day, expect partly sunny skies and about a 40% chance of showers and thunderstorms between 1 p.m. and 3 p.m., with a high near 84°F and light south winds around 5 to 6 mph.
Afternoon Pop-Up Storms Could Snag Lunch Plans
After a relatively quiet late morning, the atmosphere looks primed for scattered storms to bubble up in the early afternoon, with the best window for activity from about 1 p.m. to 3 p.m. Brief heavy downpours, frequent lightning, and quick street ponding are the main concerns, so expect short and localized impacts to commutes and outdoor events. If you have midday outdoor plans, keep a rain jacket handy and know where you can duck into shelter if a storm drifts overhead.
Thursday Night Into Friday Flood Threat
The bigger issue arrives Thursday evening, June 25, 2026, into Friday morning, June 26, 2026, when multiple waves of storms could roll through and wring out heavy, efficient rainfall. Localized totals of 1 to 4 inches or more are on the table. The highest risk for excessive rainfall and flash flooding is expected along and south of the I-70 corridor and across the Lower Missouri River basin, where storms could train over the same areas and trigger rapid runoff. Stay alert for any watches or warnings and do not drive through flooded roadways, according to the National Weather Service.
Heat Roars Back By The Weekend
Once the frontal zone lifts out, temperatures bounce back late in the weekend. Highs are expected to climb near 95°F on Sunday, June 28, 2026, and could top out around 97°F on Monday, June 29, 2026, with muggy overnight lows stuck in the mid 70s. That combination will make outdoor activity uncomfortable and potentially risky for vulnerable people, so plan on spending the hottest part of the afternoon in air-conditioned spaces when you can.
Planning Ahead And Staying Safe
If you have evening plans, including fans heading to Busch Stadium tonight, you can expect only a small chance of showers and an otherwise muggy, warm night. Even with the low rain risk, it is smart to allow extra travel time and have a shelter plan in mind if a stray storm pops up.
For heat relief later in the week, the city maintains a list of cooling centers and related resources. You can call 2-1-1 or check local locations and hours as conditions evolve through the City of St. Louis.
