St. Louis is forecast to reach about 92 degrees Wednesday under partly sunny skies, then turn sharply cooler as rain and thunderstorms move in Thursday and Friday. The main concern is the period from Thursday afternoon into Friday morning, when showers could become more widespread.
Rain may become widespread Thursday night
Showers and thunderstorms are possible Thursday afternoon, with the better chance later in the day. The high should reach about 88 degrees, with temperatures remaining warm through the afternoon. The forecast gives Thursday night an 80% chance of precipitation.
Showers and thunderstorms may continue into Friday morning, with rain likely tapering before 1 p.m. The forecast notes that heavier rain upstream could affect Missouri and Mississippi River levels later this weekend and early next week, but it does not specify resulting river levels or impacts.
Past flooding is context, not a prediction
A separate event shows why heavy rain can create serious local hazards: on July 26, 2022, the National Weather Service St. Louis reported multiple swift-water rescues and flooding on interstates and in homes across the metropolitan area. That incident is historical context, not a forecast of impacts from this storm.
For heavy-rain preparation, the Metropolitan St. Louis Sewer District advises drivers who encounter a flooded street to turn around and use another route, and recommends clearing leaves, branches and other blockages from gutters.
Cooler, drier weather follows
Friday’s high should reach about 71 degrees, down from Wednesday’s forecast high of 92, with north winds between 8 and 12 mph. Saturday is expected to be mostly sunny with a high near 70; Sunday sunny near 73; and Monday bright around 68. Overnight lows are forecast mostly in the upper 40s and 50s.
Regional flood warnings were active. Thursday night and Friday morning could still bring slick roads, reduced visibility and difficult conditions for outdoor plans.
