7-Day Forecast 38.94°N 90.45°W (Text-Only)
NWS Forecast for: St. Charles County Smartt Airport MO
Issued by: National Weather Service Saint Louis, MO
Last Update: 1:41 am CDT Jul 21, 2026




Overnight: Mostly cloudy, with a low around 79. Southwest wind around 6 mph.

Tuesday: A 30 percent chance of showers and thunderstorms, mainly before 7am. Mostly cloudy, then gradually becoming sunny, with a high near 94. Heat index values as high as 100. Northwest wind 7 to 15 mph.

Tuesday Night: Mostly clear, with a low around 68. North wind 8 to 14 mph.

Wednesday: Mostly sunny, with a high near 82. North wind 8 to 13 mph.

Wednesday Night: Partly cloudy, with a low around 62. Northeast wind 5 to 10 mph.

Thursday: Mostly sunny, with a high near 81.

Thursday Night: Partly cloudy, with a low around 62.

Friday: A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 80. Chance of precipitation is 40%.

Friday Night: A 20 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 64.

Saturday: Mostly sunny, with a high near 88.

Saturday Night: Mostly clear, with a low around 68.

Sunday: Sunny, with a high near 94.

Sunday Night: Partly cloudy, with a low around 72.

Monday: Mostly sunny, with a high near 94.



St. Charles County Smartt Airport MO
 38.94°N 90.45°W (Elev. 427 ft)

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