Weather forecast for 10 daysO'Fallon, IL
Weather forecast for the weekend
Sunday Oct 18, 2026
- 66°F
- 39°F
Sunny
- Precip. probability: 4%
- Precipitation: 0"
- Wind: 7mphSSE 165°
- Humidity: 54%
- UV index: 5
- Sunrise: 7:12 am CDT
- Sunset: 6:17 pm CDT
- details ▼
Tomorrow, on Sunday, clear and sunny conditions are also expected.
A significant variation in temperature is predicted, ranging from a high of a comfortable 66.2°F to a low of a wintry 39.2°F.
Tomorrow's forecasted high will be in line with October's typical peak of 66.6°F.
Sunrise will be at 7:12 am and sunset at 6:17 pm; tomorrow's daylight will last for 11h and 5min.
A significant variation in temperature is predicted, ranging from a high of a comfortable 66.2°F to a low of a wintry 39.2°F.
Tomorrow's forecasted high will be in line with October's typical peak of 66.6°F.
Sunrise will be at 7:12 am and sunset at 6:17 pm; tomorrow's daylight will last for 11h and 5min.
10-day overview
Daily temperatures
Warmest day: Sunday 25.10. 82°C.
Coldest day: tomorrow 66°C.
Coldest day: tomorrow 66°C.
Chance of precipitation
Highest chance: Monday - Monday 5%.
Long-term weather forecast
- Saturday
- Oct 17, 2026
- min.
- 37°F
Clear
- Precip. probability: 4%
- Precipitation: 0"
- Wind: 2mphSE 137°
- Humidity: 86%
- UV index: 0
- Sunrise: 7:11 am CDT
- Sunset: 6:18 pm CDT
- details ▼
- Sunday
- Oct 18, 2026
- 66°F
- 39°F
Sunny
- Precip. probability: 4%
- Precipitation: 0"
- Wind: 7mphSSE 165°
- Humidity: 54%
- UV index: 5
- Sunrise: 7:12 am CDT
- Sunset: 6:17 pm CDT
- details ▼
- Monday
- Oct 19, 2026
- 72°F
- 41°F
Sunny
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 4mphS 173°
- Humidity: 55%
- UV index: 5
- Sunrise: 7:13 am CDT
- Sunset: 6:16 pm CDT
- details ▼
- Tuesday
- Oct 20, 2026
- 73°F
- 45°F
Mostly Sunny
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 4mphE 91°
- Humidity: 52%
- UV index: 4
- Sunrise: 7:14 am CDT
- Sunset: 6:14 pm CDT
- details ▼
- Wednesday
- Oct 21, 2026
- 75°F
- 43°F
Sunny
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 3mphWNW 284°
- Humidity: 50%
- UV index: 4
- Sunrise: 7:15 am CDT
- Sunset: 6:13 pm CDT
- details ▼
- Thursday
- Oct 22, 2026
- 77°F
- 43°F
Sunny
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 4mphNNW 345°
- Humidity: 53%
- UV index: 4
- Sunrise: 7:16 am CDT
- Sunset: 6:12 pm CDT
- details ▼
- Friday
- Oct 23, 2026
- 79°F
- 46°F
Mostly Sunny
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 6mphESE 108°
- Humidity: 51%
- UV index: 4
- Sunrise: 7:17 am CDT
- Sunset: 6:10 pm CDT
- details ▼
- Saturday
- Oct 24, 2026
- 81°F
- 46°F
Partly Cloudy
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 6mphSE 142°
- Humidity: 50%
- UV index: 4
- Sunrise: 7:18 am CDT
- Sunset: 6:09 pm CDT
- details ▼
- Sunday
- Oct 25, 2026
- 82°F
- 48°F
Partly Cloudy
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 6mphSSW 212°
- Humidity: 50%
- UV index: 4
- Sunrise: 7:19 am CDT
- Sunset: 6:08 pm CDT
- details ▼
- Monday
- Oct 26, 2026
- 79°F
- 46°F
Partly Cloudy
- Precip. probability: 5%
- Precipitation: 0"
- Wind: 6mphSSW 208°
- Humidity: 50%
- UV index: 4
- Sunrise: 7:20 am CDT
- Sunset: 6:06 pm CDT
- details ▼
It is expected that a combination of mostly clear and overcast weather is anticipated.
Rainfall is not predicted in O'Fallon in the upcoming days.
Temperature variation will be noticeable in the upcoming period. Highs will range from 66.2°F to 82.4°F, while the minimum temperature is forecast to range between 37.4°F and 48.2°F.
Expect the warmest day on next Sunday, with temperatures peaking at 82.4°F; with the highest temperature of 66.2°F, Sunday will be the coldest day.
Rainfall is not predicted in O'Fallon in the upcoming days.
Temperature variation will be noticeable in the upcoming period. Highs will range from 66.2°F to 82.4°F, while the minimum temperature is forecast to range between 37.4°F and 48.2°F.
Expect the warmest day on next Sunday, with temperatures peaking at 82.4°F; with the highest temperature of 66.2°F, Sunday will be the coldest day.
Updated: Oct 18, 2026 @ 00:37:08 UTC
Published by: Weather U.S. | About Us
Data Sources | weather.com | Weather
Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | weather.com | Weather
Weather Forecasting & Climate
Frequently asked questions
Tomorrow, skies will stay clear and sunny.
Tomorrow, the highest temperature will be 66.2°F, while the lowest temperature will be 39.2°F.
Tomorrow, the highest temperature will be in line with the average maximum temperature in October. The lowest temperature will be uncommonly lower than the average low of 48.7°F.
Tomorrow, the highest temperature will be in line with the average maximum temperature in October. The lowest temperature will be uncommonly lower than the average low of 48.7°F.
On Sunday, in O'Fallon, sunrise will be at 7:12 am and sunset at 6:17 pm (CDT).
In O'Fallon, the length of the day tomorrow will be 11h and 5min.
