Alton Pool Forecast

Home

National Weather Service Forecast for: St. Charles County
Issued by: NWS National Weather Service Saint Louis, MO

Updated: 613 PM CDT Thu May 14 2026

St. Charles , MO

Tonight Thunder storm	Friday Thunder storm	Friday Night Thunder storm	Saturday Thunder storm	Saturday Night Thunder storm	Sunday Mostly Clear	Sunday Night Mostly Clear	Monday Thunder storm	Monday Night Thunder storm
Lo ≈55°F	Hi ≈85°F	Lo ≈65°F	Hi ≈85°F	Lo ≈65°F	Hi ≈90°F	Lo ≈70°F	Hi ≈90°F	Lo ≈75°F

Tonight	Partly cloudy this evening, then mostly cloudy with a chance of showers and thunderstorms after midnight. Lows in the mid 50s. Southeast winds 5 to 10 mph with gusts up to 20 mph. Chance of rain 50 percent.
Friday	Mostly cloudy with a chance of showers and thunderstorms in the morning, then mostly sunny with a slight chance of showers in the afternoon. Highs in the lower 80s. South winds 10 to 15 mph with gusts up to 25 mph. Chance of rain 50 percent.
Friday Night	Mostly cloudy. A chance of showers with a slight chance of thunderstorms after midnight. Not as cool with lows in the mid 60s. South winds 5 to 10 mph with gusts up to 20 mph. Chance of rain 30 percent.
Saturday	A chance of thunderstorms. Showers likely, mainly in the morning. Highs in the mid 80s. South winds 10 to 15 mph. Chance of rain 70 percent.
Saturday Night	Mostly cloudy with a chance of showers with a slight chance of thunderstorms in the evening, then partly cloudy after midnight. Lows in the mid 60s. South winds 5 to 10 mph. Chance of rain 50 percent.
Sunday	Mostly clear. Highs around 90.
Sunday Night	Mostly clear. Lows around 70.
Monday	Partly cloudy. A chance of showers and thunderstorms. Highs around 90.
Monday Night	Partly cloudy. A chance of showers and thunderstorms. Lows in the lower 70s.
Tuesday	Partly sunny. A chance of showers with a slight chance of thunderstorms in the morning, then showers likely with a chance of thunderstorms in the afternoon. Highs in the upper 80s. Chance of rain 70 percent.
Tuesday Night	Showers likely with a slight chance of thunderstorms. Lows in the lower 60s. Chance of rain 70 percent.
Wednesday	Partly sunny with a chance of showers. A slight chance of thunderstorms in the morning, then a chance of thunderstorms in the afternoon. Highs in the upper 70s. Chance of rain 50 percent.
Wednesday Night	Mostly cloudy. A slight chance of showers and thunderstorms in the evening, then a chance of showers after midnight. Lows in the upper 50s. Chance of rain 40 percent.
Thursday	Partly sunny with a slight chance of showers and thunderstorms. Highs in the upper 70s. Chance of rain 20 percent.
Zone Forecast	St. Charles County

Forecast from NOAA-NWS for St. Charles County. (Zone forecast)