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

Fri 5/1
Cloudy Weather
Day 59°
Night 39°
18
Sat 5/2
Cloudy Weather
Day 64°
Night 43°
1
Sun 5/3
Cloudy Weather
Day 73°
Night 48°
25
Mon 5/4
Partly Sunny with Showers
Day 73°
Night 54°
80
Tue 5/5
Cloudy Weather
Day 70°
Night 48°
49
Wed 5/6
Sunny Weather
Day 68°
Night 48°
0
Thu 5/7
Rainy Weather
Day 68°
Night 46°
75
Fri 5/8
Rainy Weather
Day 70°
Night 50°
55
Sat 5/9
Cloudy Weather
Day 66°
Night 54°
2
Sun 5/10
Cloudy Weather
Day 73°
Night 52°
20
Mon 5/11
Rainy Weather
Day 68°
Night 55°
55
Tue 5/12
Cloudy Weather
Day 72°
Night 48°
Wed 5/13
Cloudy Weather
Day 68°
Night 48°
Thu 5/14
Cloudy Weather
Day 70°
Night 48°
Fri 5/15
Sunny Weather
Day 70°
Night 48°
Sat 5/16
Cloudy Weather
Day 70°
Night 52°
Sun 5/17
Sunny Weather
Day 73°
Night 55°
Mon 5/18
Cloudy Weather
Day 79°
Night 59°
Tue 5/19
Cloudy Weather
Day 79°
Night 59°
Wed 5/20
Cloudy Weather
Day 79°
Night 61°
Thu 5/21
Cloudy Weather
Day 81°
Night 61°
Fri 5/22
Cloudy Weather
Day 79°
Night 59°
Sat 5/23
Sunny Weather
Day 81°
Night 61°
Sun 5/24
Cloudy Weather
Day 81°
Night 63°
Mon 5/25
Cloudy Weather
Day 81°
Night 61°
Tue 5/26
Cloudy Weather
Day 79°
Night 57°
Wed 5/27
Sunny Weather
Day 79°
Night 55°
Thu 5/28
Sunny Weather
Day 77°
Night 57°
Fri 5/29
Sunny Weather
Day 81°
Night 61°
Sat 5/30
Sunny Weather
Day 82°
Night 63°
Sun 5/31
Sunny Weather
Day 82°
Night 63°

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