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O'Fallon, MO

91°F
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O'Fallon

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O'Fallon, MO Weather
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Winter Center

Today

Hourly 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities
Heat Advisory

Today's Weather

Wed, Sep 16

Very hot and humid with intervals of clouds and sunshine; a morning shower in spots followed by a thunderstorm in spots this afternoon Hi: 93°

Tonight: A thunderstorm in spots this evening; otherwise, partly cloudy, very warm and humid Lo: 72°

Current Weather

4:15 PM

91°F
RealFeel® 101°
Mostly cloudy More Details
RealFeel Shade™ 98°
Heat Index 102°
Wind SE 2 mph
Wind Gusts 5 mph
Air Quality Poor

Looking Ahead

The intense late-season heat wave will continue into the weekend; be sure to stay hydrated

O'Fallon Weather Radar

O'Fallon Weather Radar
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Clouds
Temperature

Hourly Weather

5 PM 92°
rain drop 51%
6 PM 90°
rain drop 47%
7 PM 88°
rain drop 43%
8 PM 85°
rain drop 47%
9 PM 82°
rain drop 51%
10 PM 80°
rain drop 47%
11 PM 77°
rain drop 34%
12 AM 77°
rain drop 34%
1 AM 75°
rain drop 28%
2 AM 75°
rain drop 17%
3 AM 75°
rain drop 17%
4 AM 74°
rain drop 17%

10-Day Weather Forecast

Today

9/16

93° 72°

A t-storm around in the p.m.

Night: A t-storm around this evening

89%

Thu

9/17

97° 70°

Very hot with a stray t-storm

Partly cloudy, warm and humid

55%

Fri

9/18

94° 70°

A thunderstorm in spots

Clear, warm and humid

55%

Sat

9/19

94° 68°

Partly sunny and hot

Partly cloudy, a t-storm late

11%

Sun

9/20

88° 67°

Very warm with lots of sun

Partly cloudy, warm and humid

25%

Mon

9/21

84° 66°

Humid with a thunderstorm

Partly cloudy and warm

55%

Tue

9/22

80° 62°

Partly sunny and less humid

Mainly clear

16%

Wed

9/23

78° 59°

Clouds and sun

Partly cloudy

4%

Thu

9/24

77° 58°

A strong afternoon t-storm

Rain and a thunderstorm late

55%

Fri

9/25

79° 56°

A couple of t-storms; humid

Mainly clear

71%

Sun & Moon

12 hrs 25 mins
Rise 6:45 AM
Set 7:10 PM
Waxing Crescent
Rise 12:39 PM
Set 9:53 PM

Air Quality

See More
Air Quality Poor

The air has reached a high level of pollution and is unhealthy for sensitive groups. Reduce time spent outside if you are feeling symptoms such as difficulty breathing or throat irritation.

Allergy Outlook

See All
Tree Pollen Low Data is not supported in this location Ragweed Pollen Low Data is not supported in this location Mold Low Data is not supported in this location Grass Pollen Low Data is not supported in this location Dust & Dander Extreme Data is not supported in this location

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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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