St. Louis rolled into Wednesday, June 10, 2026, under clear skies and thick, sticky air, with morning temperatures already in the mid-70s. The afternoon heat will crank up into the mid-90s, but the bigger storyline is the one-two punch of strong storms expected late tonight and again Thursday evening.
Afternoon Heat And Humidity
Temperatures are forecast to top out near 95°F this afternoon, with heat index values peaking around 101°F. Thursday will be even hotter, with heat indices that could reach about 107°F. The muggy air will make it feel uncomfortable early and often, so it is smart to avoid strenuous activity during the hottest part of the day and stay hydrated. Southwest winds will be breezy at times, which might offer a bit of relief but can also make the heat feel more intense in direct sun and exposed spots.
Tonight's Severe Risk
Late this evening, a cold front moving in will likely trigger clusters of strong to severe thunderstorms. These storms could bring damaging wind gusts and large hail, with a low-end tornado risk especially north of Highway 36 and I‑72. The National Weather Service expects storms to form in the warm sector this afternoon, then track east of the metro area by around midnight. Anyone with evening travel or outdoor plans should be ready for sudden heavy downpours and gusty winds that can knock down tree limbs and cut power.
Thursday's Second Round
On Thursday, June 11, 2026, another frontal push late in the day is expected to fire up a second round of strong to severe storms across the region. This batch looks most likely in the late afternoon and evening. Gusty southerly winds ahead of the front and stronger storm cells could produce 25 to 30 mph gusts, with storms quickly forming clusters that increase the damaging wind and large hail threat. Evening commuters and anyone planning outdoor events should keep a close eye on the sky and be ready to head indoors quickly.
How To Prepare
For the heat, try to schedule outdoor activities earlier in the day or move them inside, and keep a fully charged phone or weather radio nearby for any warnings. The city maintains a list of cooling centers and recommends calling 2‑1‑1 for the latest locations and hours. The full list is available on the City of St. Louis website.
When storms roll in, shelter inside a sturdy building away from windows, and avoid driving through flooded roads or anywhere near downed power lines. With two rounds on tap, it is a good night and next day to keep the weather apps and flashlights handy.
