St. Louis is waking up to light rain, muggy air, and a Flood Watch this morning, Friday, June 26, 2026, with the real trouble set to build as the day goes on. Temperatures are hovering near 70°F and should climb toward a high around 81°F, while showers and thunderstorms become more widespread by midday. Forecasters warn that some storms could drop heavy, efficient rainfall capable of triggering flash flooding in low‑lying and poor‑drainage spots.
Afternoon Flood Risk
A Flood Watch is posted for much of the metro through about 7 p.m. Friday, calling for multiple rounds of thunderstorms that could bring heavy downpours and localized flooding. The National Weather Service urges residents to steer clear of standing water, avoid walking or driving through flooded areas, and move vehicles to higher ground when possible.
Timing And Commute Impacts
Showers and storms are most likely before 2 p.m., with additional waves possible into the evening as a stalled front lifts north and recharges storm development. Expect ponding on side streets, slower travel, and reduced visibility on busy routes; if you have to be on the road, take it easy, give yourself extra time, and avoid low‑water crossings.
Heat Spike Next Week
Once the front finally clears out, the pattern flips fast. Sunday turns hot with highs near 94°F, and temperatures are projected to surge into the upper 90s from Monday through Wednesday. The National Weather Service expects heat indices to push into the 100–110°F range, and a Heat Advisory or Excessive Heat Warning may be needed as a strong ridge builds over the region.
Where To Cool Off
For anyone especially sensitive to high heat, the City of St. Louis maintains a list of cooling centers and opens additional community locations during declared heat emergencies. Calling 2‑1‑1 will get you the latest details. That page includes libraries, senior centers, and other community hubs, along with addresses and hours.
Bottom Line
Heavy rain and potential flash flooding are the main threats through this afternoon and evening, so be ready to change outdoor plans and follow local advisories. After that, gear up for a quick warm‑up late this weekend and an extended stretch of dangerous heat early next week.
