Weather forecast for 10 daysO'Fallon, MO

Weather forecast for the weekend

Saturday Oct 17, 2026

  • 61°F
  • 37°F
Sunny
Sunny
  • Precip. probability: 0%
  • Precipitation: 0"
  • Wind: 3mphNE 42°
  • Humidity: 45%
  • UV index: 5
  • Sunrise: 7:14 am CDT
  • Sunset: 6:21 pm CDT
  • ▼
Today, on Saturday, October 17, sunny and dry conditions are anticipated.
Temperatures will oscillate between an enjoyable 60.8°F at their highest and a cold 37.4°F at their lowest.
Today, the maximum temperature is anticipated to be a couple of degrees lower than October's climate norm of 66.2°F.
Sunrise was at 7:14 am and sunset will be at 6:21 pm; the daylight will last for 11h and 7min.

Sunday Oct 18, 2026

  • 66°F
  • 37°F
Sunny
Sunny
  • Precip. probability: 5%
  • Precipitation: 0"
  • Wind: 7mphSSE 166°
  • Humidity: 51%
  • UV index: 5
  • Sunrise: 7:15 am CDT
  • Sunset: 6:20 pm CDT
  • ▼
Tomorrow, expect bright skies and plenty of sunshine.
Substantial temperature variations are expected, soaring to a maximum of an enjoyable 66.2°F and descending to a minimum of a cold 37.4°F.
The maximum temperature tomorrow is anticipated to reflect October's average high of 66.2°F.
Sunrise will be at 7:15 am and sunset at 6:20 pm; tomorrow's daylight will last for 11h and 5min.

10-day overview

Daily temperatures

Warmest period: Friday - Sunday 81°C.
Coldest day: today 61°C.

Chance of precipitation

Highest chance: Monday 26.10. 20%.

Long-term weather forecast

  • Saturday
  • Oct 17, 2026
  • 61°F
  • 37°F
Sunny
Sunny
  • Precip. probability: 0%
  • Precipitation: 0"
  • Wind: 3mphNE 42°
  • Humidity: 45%
  • UV index: 5
  • Sunrise: 7:14 am CDT
  • Sunset: 6:21 pm CDT
  • ▼
  • Sunday
  • Oct 18, 2026
  • 66°F
  • 37°F
Sunny
Sunny
  • Precip. probability: 5%
  • Precipitation: 0"
  • Wind: 7mphSSE 166°
  • Humidity: 51%
  • UV index: 5
  • Sunrise: 7:15 am CDT
  • Sunset: 6:20 pm CDT
  • ▼
  • Monday
  • Oct 19, 2026
  • 72°F
  • 41°F
Partly Cloudy
Partly Cloudy
  • Precip. probability: 6%
  • Precipitation: 0"
  • Wind: 4mphSSE 162°
  • Humidity: 54%
  • UV index: 5
  • Sunrise: 7:16 am CDT
  • Sunset: 6:18 pm CDT
  • ▼
  • Tuesday
  • Oct 20, 2026
  • 73°F
  • 43°F
Partly Cloudy
Partly Cloudy
  • Precip. probability: 9%
  • Precipitation: 0"
  • Wind: 4mphSE 145°
  • Humidity: 53%
  • UV index: 4
  • Sunrise: 7:17 am CDT
  • Sunset: 6:17 pm CDT
  • ▼
  • Wednesday
  • Oct 21, 2026
  • 77°F
  • 45°F
Mostly Sunny
Mostly Sunny
  • Precip. probability: 5%
  • Precipitation: 0"
  • Wind: 3mphS 187°
  • Humidity: 53%
  • UV index: 4
  • Sunrise: 7:18 am CDT
  • Sunset: 6:16 pm CDT
  • ▼
  • Thursday
  • Oct 22, 2026
  • 79°F
  • 45°F
Partly Cloudy
Partly Cloudy
  • Precip. probability: 5%
  • Precipitation: 0"
  • Wind: 4mphS 179°
  • Humidity: 52%
  • UV index: 4
  • Sunrise: 7:19 am CDT
  • Sunset: 6:14 pm CDT
  • ▼
  • Friday
  • Oct 23, 2026
  • 81°F
  • 46°F
Mostly Sunny
Mostly Sunny
  • Precip. probability: 5%
  • Precipitation: 0"
  • Wind: 6mphSE 134°
  • Humidity: 50%
  • UV index: 4
  • Sunrise: 7:20 am CDT
  • Sunset: 6:13 pm CDT
  • ▼
  • Saturday
  • Oct 24, 2026
  • 81°F
  • 48°F
Partly Cloudy
Partly Cloudy
  • Precip. probability: 4%
  • Precipitation: 0"
  • Wind: 6mphSSE 150°
  • Humidity: 50%
  • UV index: 4
  • Sunrise: 7:21 am CDT
  • Sunset: 6:12 pm CDT
  • ▼
  • Sunday
  • Oct 25, 2026
  • 81°F
  • 52°F
Partly Cloudy
Partly Cloudy
  • Precip. probability: 7%
  • Precipitation: 0"
  • Wind: 6mphSW 215°
  • Humidity: 54%
  • UV index: 4
  • Sunrise: 7:22 am CDT
  • Sunset: 6:11 pm CDT
  • ▼
  • Monday
  • Oct 26, 2026
  • 79°F
  • 52°F
Partly Cloudy
Partly Cloudy
  • Precip. probability: 20%
  • Precipitation: 0"
  • Wind: 5mphWSW 254°
  • Humidity: 58%
  • UV index: 4
  • Sunrise: 7:23 am CDT
  • Sunset: 6:09 pm CDT
  • ▼
For the next ten days, a combination of cloudy and dry and sunny weather is anticipated.
Rain is not expected in O'Fallon in the upcoming days.
There will be a considerable variation in temperature in the upcoming days. Highs will range from 60.8°F to 80.6°F, while the lowest night temperatures will vary also significantly, as the minimum temperature is expected to range between 37.4°F and 51.8°F.
Friday through next Sunday, with the highest temperature of 80.6°F, will be the warmest days in O'Fallon; today is the coldest day, with a maximum temperature of 60.8°F.
Updated: Oct 17, 2026 @ 15:42:28 UTC
Published by: Weather U.S. | About Us
Data Sources | weather.com | Weather
Weather Forecasting & Climate

Frequently asked questions

On Saturday, in O'Fallon, the weather remains calm, bright, and sunny.

Today, the maximum temperature will be 60.8°F, while the minimum temperature will be 37.4°F.
The maximum temperature today will be a few degrees lower than the average highest temperature in October. The lowest temperature will be notably lower than the average low of 48.7°F.

On Saturday, in O'Fallon, sunrise was at 7:14 am and sunset will be at 6:21 pm (CDT).

In O'Fallon, today, there will be 11h and 7min of daylight.

On Sunday, skies are expected to be clear and full of sunshine.

Tomorrow, the highest temperature will be 66.2°F, while the lowest temperature will be 37.4°F.
The highest temperature tomorrow will be in line with the average maximum temperature in October. The lowest temperature will be significantly lower than the average low of 48.7°F.

On Sunday, in O'Fallon, sunrise will be at 7:15 am and sunset at 6:20 pm (CDT).

In O'Fallon, tomorrow, there will be 11h and 5min of daylight.