St. Louis woke up to a classic Midwestern summer combo on Friday, July 10, 2026: muggy air, mostly clear skies, and mid-70s temperatures that already felt sticky before breakfast. The calm will not last. A round of strong thunderstorms is expected later today and into the night, and a Flash Flood Watch is in effect for parts of southeast Missouri and southwest Illinois through Saturday morning.
Afternoon Storms Set The Stage
This afternoon brings isolated to scattered thunderstorms, with a slight chance of a shower or storm between about 4:00 and 5:00 p.m. local time as highs climb near 90°F. The risk ramps up later in the day as storms build in from the west. Gusty winds and brief, heavy downpours could quickly cut visibility and leave standing water on low-lying streets, especially during the evening drive.
Overnight: Biggest Flood Risk
Radar and forecasts show that 1 to 3 inches of rain have already fallen across parts of central and southeast Missouri, with isolated pockets of 5 to more than 7 inches in a narrow corridor over southern Crawford into Iron, Reynolds and Madison counties - and more heavy rain is possible tonight. With the ground already soaked, any additional downpours could trigger rapid urban and small-stream flash flooding in the watch area.
The main threats are heavy rain and damaging wind gusts, especially from late evening into the overnight hours, according to the National Weather Service.
Weekend And Early Week Outlook
Conditions trend drier on Sunday and into next week, with highs returning to the upper 80s and 90s by midweek and lower chances for storms. If tonight's flood-producing storms miss your neighborhood, they are more likely to pass to the south, but localized pockets of heavy rain remain possible through Saturday morning.
How To Get Ready Tonight
Expect slower going on the roads this evening and give yourself extra travel time. Avoid driving through standing water, and move vehicles out of low spots if you can. Before you head out, especially if you are riding MetroLink or MetroBus, check for service updates at Metro Transit and keep an eye on local alerts.
