Weather
St. Louis Area Weather Update: Sunny but Chilly Oct 17-18
St. Louis, MO – A dramatic shift in temperatures will reshape the weekend across the St. Louis metropolitan area as Thursday's warmth and thunderstorms give way to brisk winds, cooler afternoons and n
By Nora Whitfield · 2026-10-15T08:11:16.739Z
St. Louis, MO – A dramatic shift in temperatures will reshape the weekend across the St. Louis metropolitan area as Thursday's warmth and thunderstorms give way to brisk winds, cooler afternoons and nighttime temperatures dipping into the upper 30s. After reaching approximately 81 degrees Thursday, the region will experience a noticeable cooldown Friday, followed by a chilly Saturday night with temperatures near 39 degrees. The changing conditions could catch residents off guard, particularly those planning outdoor activities or early morning travel.
According to the National Weather Service in St. Louis, showers and thunderstorms are likely Thursday, with a 70% chance of precipitation. Rain chances increase during the morning, with showers and possibly a thunderstorm between 8 a.m. and 1 p.m. Patchy fog could develop between 10 a.m. and 11 a.m., while afternoon temperatures climb to around 81 degrees before cooler weather begins moving into the region.
Cooler Air Arrives Behind Thursday's Storms Thursday night marks the beginning of the transition, with showers and thunderstorms likely before 1 a.m. and scattered showers possible through approximately 2 a.m. The precipitation probability remains at 70%, while southwest winds of 9 to 15 mph shift northwest after midnight. Gusts could reach 24 mph as temperatures fall toward 50 degrees by Friday morning.
The cooldown becomes more noticeable Friday, when afternoon highs struggle to reach 57 degrees, approximately 24 degrees below Thursday's projected high. Northwest winds of 16 to 18 mph could gust as high as 29 mph, adding a brisk feel to the afternoon. Despite partly sunny skies, residents spending extended periods outdoors may want heavier jackets as cooler air settles across the metropolitan area.
Weekend Temperatures Fall Into the Upper 30s Saturday brings improving weather conditions but continued cool temperatures. Sunshine is expected throughout the day, with afternoon highs near 60 degrees. However, temperatures will fall quickly after sunset, reaching approximately 39 degrees early Sunday morning. That represents a 42 degree difference between Thursday's afternoon high and the weekend's coldest forecast temperature, although the decline unfolds over multiple days rather than within a single afternoon.
The forecast does not indicate freezing temperatures for the St. Louis forecast location, but the upper 30s readings could make early morning outdoor activities uncomfortable. Residents attending sporting events, visiting parks or working outside Saturday evening should prepare for colder conditions. The weekend cooldown will also provide a noticeable reminder that fall weather is becoming more established across eastern Missouri.
Travel Conditions and Next Week's Outlook Drivers using Interstate 64, Interstate 70, Interstate 44 and Interstate 55 should be prepared for potentially wet pavement during Thursday's showers. Patchy morning fog could briefly reduce visibility in some locations, while Friday's stronger northwest winds may be noticeable on exposed roadways and bridges. No specific highway closures or travel disruptions are identified in the supplied forecast.
By Sunday, temperatures begin recovering as sunshine pushes afternoon highs toward 67 degrees following a chilly morning. The warming trend continues Monday, with highs near 72 degrees, followed by approximately 74 degrees Tuesday and 77 degrees Wednesday. The National Weather Service forecast indicates mostly sunny or sunny conditions during this stretch, suggesting a more comfortable period for outdoor plans after the weekend cooldown.
Will the cooler weekend temperatures change your outdoor plans, or are you looking forward to the return of fall weather?
Five Day Weather Outlook Thursday 10/15: Showers and thunderstorms are likely, with a 70% precipitation chance and afternoon highs near 81 degrees. Patchy morning fog is possible before skies begin clearing later, followed by nighttime lows around 50 degrees.
Friday 10/16: Partly sunny skies accompany a sharp cooldown, with highs near 57 degrees and northwest winds gusting up to 29 mph. Friday night turns mostly cloudy, with lows around 41 degrees.
Saturday 10/17: Sunshine returns across the St. Louis area, with afternoon temperatures reaching approximately 60 degrees. Clear skies Saturday night allow temperatures to fall near 39 degrees, creating a chilly start to Sunday.
Sunday 10/18: Sunny skies and warmer afternoon temperatures provide improving conditions for outdoor activities, with highs around 67 degrees. Mostly clear skies continue Sunday night as temperatures settle near 43 degrees.
Monday 10/19: Mostly sunny conditions continue as temperatures climb to approximately 72 degrees, extending the warming trend. Monday night brings partly cloudy skies and lows near 46 degrees, with no precipitation probability specified.
Extended Outlook: October 20 21 Tuesday is expected to bring sunshine and highs near 74 degrees, followed by mostly clear conditions and lows around 49 degrees Tuesday night.
Wednesday continues the warming trend with sunny skies and afternoon highs near 77 degrees. The supplied forecast does not extend beyond Wednesday, and no additional significant weather threats are identified in the available outlook.