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Northeast weather to feel more like Thanksgiving than Memorial Day. See the temp forecast. Chevron right

O'Fallon, MO

64°F
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O'Fallon

Missouri

64°
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O'Fallon, MO Weather
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May 22 - June 5

Fri 5/22

67° /61°
49%
Cloudy with a brief shower or two

RealFeel®66°

RealFeel Shade™64°

Max UV Index2.0 (Low)

WindENE 7 mph

Hours of Precipitation2.5

Hours of Rain2.5

Sat 5/23

78° /62°
55%
Cloudy with a thunderstorm in spots late in the afternoon

RealFeel®79°

RealFeel Shade™77°

Max UV Index3.0 (Moderate)

WindW 5 mph

Hours of Precipitation1

Hours of Rain1

Sun 5/24

81° /60°
55%
Cloudy with a thunderstorm in spots early in the morning, then times of clouds and sun in the afternoon

RealFeel®84°

RealFeel Shade™79°

Max UV Index5.0 (Moderate)

WindNNW 6 mph

Hours of Precipitation1

Hours of Rain1

Mon 5/25

81° /64°
55%
Variable clouds with a thunderstorm in parts of the area

RealFeel®85°

RealFeel Shade™79°

Max UV Index4.0 (Moderate)

WindE 6 mph

Hours of Precipitation1

Hours of Rain1

Tue 5/26

79° /65°
72%
Cloudy and humid with a couple of showers

RealFeel®83°

RealFeel Shade™79°

Max UV Index3.0 (Moderate)

WindE 7 mph

Hours of Precipitation2

Hours of Rain2

Wed 5/27

78° /64°
87%
Cloudy and humid; a couple of morning thunderstorms followed by occasional rain and a thunderstorm in the afternoon

RealFeel®80°

RealFeel Shade™80°

Max UV Index4.0 (Moderate)

WindESE 7 mph

Hours of Precipitation3.5

Hours of Rain3.5

Thu 5/28

80° /62°
55%
Still cloudy and humid; a thundershower in the morning followed by a thunderstorm in parts of the area in the afternoon

RealFeel®85°

RealFeel Shade™82°

Max UV Index3.0 (Moderate)

WindENE 6 mph

Hours of Precipitation1

Hours of Rain1

Fri 5/29

80° /61°
0%
Less humid with sun through high clouds

RealFeel®79°

RealFeel Shade™77°

Max UV Index5.0 (Moderate)

WindENE 9 mph

Sat 5/30

77° /57°
1%
Low humidity with plenty of sunshine

RealFeel®83°

RealFeel Shade™74°

Max UV Index11.0 (Extreme)

WindNE 6 mph

Sun 5/31

76° /58°
0%
Mostly sunny

RealFeel®81°

RealFeel Shade™74°

Max UV Index11.0 (Extreme)

WindNE 7 mph

Mon 6/1

81° /61°
60%
Humid with periods of rain

RealFeel®86°

RealFeel Shade™81°

Max UV Index3.0 (Moderate)

WindNNW 6 mph

Hours of Precipitation4

Hours of Rain4

Tue 6/2

80° /64°
55%
Humid with clouds breaking for some sun; a little morning rain followed by a shower in spots in the afternoon

RealFeel®92°

RealFeel Shade™83°

Max UV Index10.0 (Very High)

WindNNW 5 mph

Hours of Precipitation2.5

Hours of Rain2.5

Wed 6/3

81° /62°
55%
Cloudy and humid with a little rain

RealFeel®87°

RealFeel Shade™82°

Max UV Index5.0 (Moderate)

WindWNW 7 mph

Hours of Precipitation2.5

Hours of Rain2.5

Thu 6/4

80° /60°
63%
Mostly cloudy and humid with a couple of showers and a thunderstorm

RealFeel®84°

RealFeel Shade™83°

Max UV Index3.0 (Moderate)

WindSW 10 mph

Hours of Precipitation3

Hours of Rain3

Fri 6/5

81° /63°
25%
Partly sunny and humid

RealFeel®92°

RealFeel Shade™83°

Max UV Index11.0 (Extreme)

WindN 2 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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