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Today Hourly 7 days 30 days December
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December 2026 Weather | O'Fallon, Missouri

Tue 12/1
Cloudy Weather
Day 54°
Night 30°
80
Wed 12/2
Cloudy Weather
Day 39°
Night 28°
3
Thu 12/3
Cloudy Weather
Day 45°
Night 32°
Fri 12/4
Cloudy Weather
Day 54°
Night 34°
Sat 12/5
Cloudy Weather
Day 52°
Night 36°
4
Sun 12/6
Cloudy Weather
Day 41°
Night 27°
Mon 12/7
Cloudy Weather
Day 39°
Night 23°
25
Tue 12/8
Cloudy Weather
Day 37°
Night 21°
Wed 12/9
Sunny Weather
Day 37°
Night 25°
65
Thu 12/10
Cloudy Weather
Day 45°
Night 28°
Fri 12/11
Cloudy Weather
Day 45°
Night 28°
13
Sat 12/12
Sunny Weather
Day 48°
Night 27°
Sun 12/13
Sunny Weather
Day 46°
Night 28°
Mon 12/14
Cloudy Weather
Day 39°
Night 25°
Tue 12/15
Cloudy Weather
Day 43°
Night 25°
Wed 12/16
Cloudy Weather
Day 41°
Night 28°
0
Thu 12/17
Icy Road Conditions
Day 43°
Night 27°
Fri 12/18
Snowy Weather
Day 39°
Night 19°
Sat 12/19
Snowy Weather
Day 37°
Night 19°
Sun 12/20
Snowy Weather
Day 36°
Night 18°
4
Mon 12/21
Snowy Weather
Day 34°
Night 19°
Tue 12/22
Cloudy Weather
Day 36°
Night 25°
Wed 12/23
Cloudy Weather
Day 39°
Night 25°
25
Thu 12/24
Snowy Weather
Day 37°
Night 25°
1
Fri 12/25
Snowy Weather
Day 36°
Night 18°
Sat 12/26
Cloudy Weather
Day 36°
Night 18°
Sun 12/27
Cloudy Weather
Day 36°
Night 18°
Mon 12/28
Cloudy Weather
Day 36°
Night 18°
Tue 12/29
Cloudy Weather
Day 34°
Night 21°
Wed 12/30
Cloudy Weather
Day 34°
Night 19°
0
Thu 12/31
Snowy Weather
Day 36°
Night 16°

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