Saint Charles, MO Weather Forecast

Local 7-day forecast

83°
F

Mostly Sunny

Track current conditions, temperature changes, wind, and the full daily outlook for Saint Charles, MO in one place.

Sunday, August 23, 2026
Wind: 6 mph NW
This Afternoon

Mostly sunny, with a high near 83. Northwest wind around 6 mph.

Local 7-day forecast

Local Weather Overview

This forecast page for Saint Charles, MO is designed for quick trip planning, giving you a clean read on daytime highs, overnight lows, and changing conditions across the upcoming forecast window. Latest sync: Aug 23, 2026 6:50 PM CDT.

The active forecast window currently covers Aug 23 to Aug 29, 2026 for Saint Charles, MO.

Page Snapshot

Page focus
city weather
Forecast window
Aug 23 to Aug 29, 2026
Latest sync
Aug 23, 2026 6:50 PM CDT
Forecast office
LSX
Source
NOAA / NWS
Next High
83°F
This Afternoon
Next Low
59°F
Tonight
Rain Outlook
3
Periods mentioning precipitation
Windiest
3 to 8 mph
Thursday

Daily Outlook

Today
Aug 23
Mostly Sunny
83 °F
/ 59°F
Wind 6 mph
Mon
Aug 24
Areas Of Fog then Mostly Sunny
84 °F
/ 63°F
Wind 0 to 3 mph
Tue
Aug 25
Mostly Sunny
87 °F
/ 69°F
Wind 6 mph
Wed
Aug 26
Mostly Sunny
90 °F
/ 68°F
Wind 2 to 6 mph
Thu
Aug 27
Sunny
88 °F
/ 66°F
Wind 3 to 8 mph
Fri
Aug 28
Sunny
87 °F
/ 68°F
Wind 0 to 3 mph
Sat
Aug 29
Slight Chance Rain Showers
89 °F
/ 73°F
Wind 3 to 7 mph

This Week in Saint Charles

Wednesday looks like the warmest upcoming period in Saint Charles at 90 degrees F.

Tonight is the coolest period ahead with temperatures near 59 degrees F.

The strongest winds are forecast for Thursday at about 3 to 8 mph NW.

Precipitation is mentioned in 3 upcoming forecast periods.

Forecast Details

Last updated
Aug 23, 2026 6:50 PM CDT
Coverage
7 days
Time zone
America/Chicago
Forecast office
LSX
Radar station
KLSX

Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.

Open NOAA source

Extended Forecast

Tonight
Aug 23
59°F
Partly Cloudy then Patchy Fog
0 to 5 mph N

Patchy fog after 5am. Partly cloudy, with a low around 59. North wind 0 to 5 mph.

Monday
Aug 24
84°F
Areas Of Fog then Mostly Sunny
0 to 3 mph E

Areas of fog before 9am. Mostly sunny, with a high near 84. East wind 0 to 3 mph.

Monday Night
Aug 24
63°F
Mostly Clear
5 mph E

Mostly clear, with a low around 63. East wind around 5 mph.

Tuesday
Aug 25
87°F
Mostly Sunny
6 mph SE

Mostly sunny, with a high near 87. Southeast wind around 6 mph.

Tuesday Night
Aug 25
69°F
Partly Cloudy
5 mph SE

Partly cloudy, with a low around 69.

Wednesday
Aug 26
90°F
Mostly Sunny
2 to 6 mph SW

Mostly sunny, with a high near 90.

Wednesday Night
Aug 26
68°F
Slight Chance Showers And Thunderstorms
5 mph W

A slight chance of showers and thunderstorms between 7pm and 1am. Mostly clear, with a low around 68. Chance of precipitation is 20%.

Thursday
Aug 27
88°F
Sunny
3 to 8 mph NW

Sunny, with a high near 88.

Thursday Night
Aug 27
66°F
Mostly Clear
0 to 6 mph N

Mostly clear, with a low around 66.

Friday
Aug 28
87°F
Sunny
0 to 3 mph N

Sunny, with a high near 87.

Friday Night
Aug 28
68°F
Partly Cloudy
3 mph E

Partly cloudy, with a low around 68.

Saturday
Aug 29
89°F
Slight Chance Rain Showers
3 to 7 mph S

A slight chance of rain showers between 7am and 1pm. Mostly sunny, with a high near 89. Chance of precipitation is 20%.

Saturday Night
Aug 29
73°F
Partly Cloudy then Slight Chance Showers And Thunderstorms
8 mph S

A slight chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 73. Chance of precipitation is 20%.

Detailed Forecast

Period Conditions Temp Wind
This Afternoon
Aug 23
Mostly Sunny
83°F
6 mph
NW
Tonight
Aug 23
Partly Cloudy then Patchy Fog
59°F
0 to 5 mph
N
Monday
Aug 24
Areas Of Fog then Mostly Sunny
84°F
0 to 3 mph
E
Monday Night
Aug 24
Mostly Clear
63°F
5 mph
E
Tuesday
Aug 25
Mostly Sunny
87°F
6 mph
SE
Tuesday Night
Aug 25
Partly Cloudy
69°F
5 mph
SE
Wednesday
Aug 26
Mostly Sunny
90°F
2 to 6 mph
SW
Wednesday Night
Aug 26
Slight Chance Showers And Thunderstorms
68°F
5 mph
W
Thursday
Aug 27
Sunny
88°F
3 to 8 mph
NW
Thursday Night
Aug 27
Mostly Clear
66°F
0 to 6 mph
N
Friday
Aug 28
Sunny
87°F
0 to 3 mph
N
Friday Night
Aug 28
Partly Cloudy
68°F
3 mph
E
Saturday
Aug 29
Slight Chance Rain Showers
89°F
3 to 7 mph
S
Saturday Night
Aug 29
Partly Cloudy then Slight Chance Showers And Thunderstorms
73°F
8 mph
S
Historic Saint Charles Main Street 3
Historic Saint Charles Main Street 3 image
Weather data provided by the National Weather Service (NOAA). Forecast pages update automatically as new periods are synced for each supported U.S. location.