St. Louis is soaking up a short-lived taste of summer on Thursday, April 16, 2026, with early clouds giving way to sunshine and afternoon highs in the low to mid 80s. The warm, breezy setup is the calm before a stronger system charges in on Friday, April 17, bringing a higher risk for organized thunderstorms that could turn severe.
Thursday: A Brief Warm-Up Before The Trouble
Clouds hang on through early morning, but skies are expected to clear by mid-morning, setting the stage for highs near 84°F and light southwest winds around 8 mph. It is prime territory for lunch on the patio or a late-day walk while the weather behaves. Rain chances drop into the low teens through the afternoon as lingering morning showers move out, although a few stubborn clouds may still drift across the river. Overnight lows stay mild in the low 60s ahead of Friday’s incoming system.
Friday: Evening Commute In The Crosshairs
A strong frontal boundary is on track to sweep east across the region Friday afternoon and evening, and forecasters say thunderstorms could organize into a line that packs a punch. Periods of damaging wind, isolated tornadoes, and pockets of large hail are possible inside the strongest storms. The most likely arrival window is late Friday afternoon through the evening, a timing that could tangle the drive home and disrupt night games, shows, and dinner plans on April 17. Stay alert for watches and warnings from the Storm Prediction Center.
Weekend: Spring Hits The Brakes
Once the front slides through on Saturday, April 18, cooler air filters in and knocks daytime highs back to the low 60s, with a brisk northwest breeze and a chance of lingering showers mainly in the morning. Sunday looks like a reset button: drier, a bit brighter, and milder with highs in the mid 60s. Early next week, temperatures start climbing again toward the low 70s. If you are planning outdoor time Saturday, expect it to feel a lot different from Thursday’s almost-summer heat.
How To Get Ready
A little prep on Friday can save a lot of scrambling later. Before storms move in, charge phones and portable batteries, pull in lightweight patio furniture or umbrellas, and make sure everyone in your household knows the nearest sturdy indoor spot to ride out strong wind or hail. If you see lightning or hear thunder, head inside immediately and avoid driving through standing water. Stronger storms can trigger brief power outages or knock down limbs and trees. Keep weather apps, local radio, or emergency alerts turned on so you can jump quickly if a watch or warning is issued.
More Reading And Updates
We dug into the area’s active spring pattern in an earlier piece; check out our April 15 forecast for added context as the week unfolds. This page will be updated if watches or warnings go up on Friday, and local officials will share any county-level alerts as conditions warrant.
