St. Louis woke up to clear skies and about 57°F on Tuesday morning, April 21, 2026, with the mercury set to climb quickly into the low 80s. Mostly sunny skies are on tap, but gusty southwest winds will add some attitude to the afternoon, especially for patios and any outdoor gear that is not tied down.
Afternoon Winds And Warmth
Highs should reach near 81°F this afternoon, with southwest winds around 6 to 15 mph and gusts as high as 25 to 30 mph. Some spots north of I-44 could see stronger gusts into the mid 30s. Wednesday is expected to stay mild near 79°F, and Thursday looks even warmer, before a slow moving system edges in with widespread rain and a chance of thunderstorms late Thursday night into Friday morning (April 23 to 24, 2026). These timing and impact details come from the National Weather Service.
Late-Week Rain Threat
The heaviest and most widespread rain is most likely late Thursday night into Friday morning (April 23 to 24), with additional rounds possible through the weekend. Drivers should be ready for wet roads, slower commutes, and brief, heavy downpours that could cut visibility on Friday morning. Anyone banking on outdoor plans from Thursday night through Friday would be wise to have a solid indoor backup in their pocket.
Plan Ahead
Use today’s pleasant weather to secure loose patio furniture and tie down lightweight canopies, and keep rain gear within easy reach for the end of the week. For background on this warm to wet pattern, see our April 15 warm-to-wet pattern forecast and check updated guidance as the system gets closer.
