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O'Fallon, MO

79°F
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O'Fallon

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O'Fallon, MO Weather
Today WinterCast Local {stormName} Tracker Hourly 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities

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May 15 - May 29

Fri 5/15

84° /67°
25%
Times of sun and clouds

RealFeel®89°

RealFeel Shade™81°

Max UV Index10.0 (Very High)

WindS 10 mph

Sat 5/16

81° /65°
91%
Mostly cloudy with a couple of showers and a heavy thunderstorm; thunderstorms could bring damaging winds, flash flooding and hail

RealFeel®82°

RealFeel Shade™79°

Max UV Index3.0 (Moderate)

WindS 7 mph

Hours of Precipitation2

Hours of Rain2

Sun 5/17

90° /73°
8%
Partly sunny and hot

RealFeel®91°

RealFeel Shade™86°

Max UV Index10.0 (Very High)

WindS 13 mph

Mon 5/18

82° /68°
58%
Windy and humid with intervals of clouds and sunshine; an afternoon thunderstorm

RealFeel®84°

RealFeel Shade™81°

Max UV Index6.0 (High)

WindS 15 mph

Hours of Precipitation1

Hours of Rain1

Tue 5/19

74° /54°
88%
Cloudy and not as warm with a couple of showers and a thunderstorm; breezy in the morning; thunderstorms can bring localized damaging wind gusts

RealFeel®75°

RealFeel Shade™72°

Max UV Index3.0 (Moderate)

WindWSW 13 mph

Hours of Precipitation4

Hours of Rain4

Wed 5/20

68° /48°
20%
Partly sunny and less humid

RealFeel®72°

RealFeel Shade™65°

Max UV Index7.0 (High)

WindN 9 mph

Thu 5/21

69° /49°
17%
Mostly sunny

RealFeel®77°

RealFeel Shade™67°

Max UV Index10.0 (Very High)

WindESE 5 mph

Fri 5/22

75° /54°
1%
Mostly sunny

RealFeel®83°

RealFeel Shade™73°

Max UV Index11.0 (Extreme)

WindSSE 6 mph

Sat 5/23

81° /60°
30%
Cloudy with a couple of showers possible

RealFeel®83°

RealFeel Shade™82°

Max UV Index5.0 (Moderate)

WindSSW 7 mph

Sun 5/24

81° /60°
30%
Mostly cloudy and humid with a thunderstorm possible

RealFeel®84°

RealFeel Shade™79°

Max UV Index4.0 (Moderate)

WindNNW 5 mph

Mon 5/25

80° /60°
35%
Mostly cloudy with a couple of showers and thunderstorms possible

RealFeel®83°

RealFeel Shade™78°

Max UV Index7.0 (High)

WindE 6 mph

Tue 5/26

81° /64°
55%
A little rain in the morning; otherwise, mostly cloudy

RealFeel®87°

RealFeel Shade™80°

Max UV Index5.0 (Moderate)

WindESE 4 mph

Hours of Precipitation1

Hours of Rain1

Wed 5/27

80° /63°
4%
Mostly cloudy and humid

RealFeel®91°

RealFeel Shade™86°

Max UV Index5.0 (Moderate)

WindESE 6 mph

Thu 5/28

79° /58°
69%
A couple of showers in the morning; otherwise, humid with intervals of clouds and sunshine

RealFeel®88°

RealFeel Shade™84°

Max UV Index6.0 (High)

WindSSW 9 mph

Hours of Precipitation1

Hours of Rain1

Fri 5/29

82° /61°
25%
Less humid with intervals of clouds and sunshine

RealFeel®88°

RealFeel Shade™79°

Max UV Index7.0 (High)

WindW 7 mph

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World North America United States Missouri O'Fallon

Weather Near O'Fallon:

  • St. Charles, MO
  • St. Louis, MO
  • St. Peters, MO
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