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

Today 5/20
Rainy Weather
Day 66°
Night 54°
55
Thu 5/21
Cloudy Weather
Day 72°
Night 59°
10
Fri 5/22
Stormy Weather
Day 66°
Night 57°
88
Sat 5/23
Stormy Weather
Day 75°
Night 61°
56
Sun 5/24
Cloudy Weather
Day 77°
Night 61°
55
Mon 5/25
Cloudy Weather
Day 79°
Night 63°
30
Tue 5/26
Rainy Weather
Day 81°
Night 63°
60
Wed 5/27
Stormy Weather
Day 79°
Night 64°
74
Thu 5/28
Stormy Weather
Day 79°
Night 63°
79
Fri 5/29
Stormy Weather
Day 81°
Night 63°
67
Sat 5/30
Rainy Weather
Day 81°
Night 64°
56
Sun 5/31
Cloudy Weather
Day 81°
Night 64°
49

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