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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 66°
Night 52°
Sat 5/2
Cloudy Weather
Day 70°
Night 50°
Sun 5/3
Cloudy Weather
Day 68°
Night 48°
Mon 5/4
Cloudy Weather
Day 72°
Night 50°
Tue 5/5
Sunny Weather
Day 75°
Night 54°
Wed 5/6
Sunny Weather
Day 75°
Night 55°
Thu 5/7
Cloudy Weather
Day 77°
Night 55°
Fri 5/8
Cloudy Weather
Day 77°
Night 55°
Sat 5/9
Stormy Weather
Day 75°
Night 55°
Sun 5/10
Rainy Weather
Day 72°
Night 52°
Mon 5/11
Cloudy Weather
Day 66°
Night 55°
Tue 5/12
Cloudy Weather
Day 70°
Night 52°
Wed 5/13
Cloudy Weather
Day 75°
Night 57°
Thu 5/14
Cloudy Weather
Day 73°
Night 50°
Fri 5/15
Cloudy Weather
Day 70°
Night 52°
Sat 5/16
Sunny Weather
Day 73°
Night 54°
Sun 5/17
Cloudy Weather
Day 79°
Night 57°
Mon 5/18
Rainy Weather
Day 73°
Night 52°
Tue 5/19
Cloudy Weather
Day 73°
Night 50°
Wed 5/20
Cloudy Weather
Day 72°
Night 52°
Thu 5/21
Cloudy Weather
Day 73°
Night 52°
Fri 5/22
Cloudy Weather
Day 72°
Night 52°
Sat 5/23
Rainy Weather
Day 72°
Night 59°
Sun 5/24
Stormy Weather
Day 77°
Night 61°
Mon 5/25
Stormy Weather
Day 79°
Night 61°
Tue 5/26
Sunny with a Chance of Thunderstorms
Day 82°
Night 61°
Wed 5/27
Rainy Weather
Day 82°
Night 63°
Thu 5/28
Stormy Weather
Day 82°
Night 63°
Fri 5/29
Cloudy Weather
Day 84°
Night 63°
Sat 5/30
Cloudy Weather
Day 84°
Night 54°
Sun 5/31
Partly Sunny with Showers
Day 75°
Night 55°

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