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Heat wave to intensify as all-time March records fall across the West. See how hot it will get. Chevron right

O'Fallon, MO

80°F
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O'Fallon

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O'Fallon, MO Weather
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Winter Center

Today

Hourly Daily Radar MinuteCast® Monthly Air Quality Health & Activities

Today's Weather

Fri, Mar 20

Mostly sunny and very warm Hi: 84°

Tonight: Mainly clear Lo: 48°

Current Weather

11:55 AM

80°F
RealFeel® 86°
Sunny More Details
RealFeel Shade™ 78°
Wind W 4 mph
Wind Gusts 10 mph
Air Quality Poor

Looking Ahead

Much cooler Monday

O'Fallon Weather Radar

O'Fallon Weather Radar
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Clouds
Temperature

Hourly Weather

12 PM 80°
rain drop 0%
1 PM 82°
rain drop 0%
2 PM 83°
rain drop 0%
3 PM 84°
rain drop 0%
4 PM 84°
rain drop 0%
5 PM 82°
rain drop 0%
6 PM 80°
rain drop 0%
7 PM 75°
rain drop 0%
8 PM 71°
rain drop 0%
9 PM 68°
rain drop 0%
10 PM 64°
rain drop 0%
11 PM 60°
rain drop 0%

10-Day Weather Forecast

Today

3/20

84° 48°

Mostly sunny and very warm

Night: Mainly clear

0%

Sat

3/21

83° 61°

Sunny and very warm

Clear; breezy late

5%

Sun

3/22

82° 41°

Partly sunny and warm

Partly cloudy; windy, cooler

1%

Mon

3/23

54° 38°

Cooler; breezy in the morning

Partly cloudy

1%

Tue

3/24

61° 43°

Clouds and sun

Clouds breaking

25%

Wed

3/25

66° 49°

Mostly cloudy

Partly cloudy

12%

Thu

3/26

74° 40°

Mostly sunny and warm

Rain and a thunderstorm early

25%

Fri

3/27

53° 32°

Morning rain; cloudy, cooler

Mostly clear

75%

Sat

3/28

59° 41°

Plenty of sun

Clear

0%

Sun

3/29

68° 47°

Abundant sunshine

Clear

0%

Sun & Moon

12 hrs 08 mins
Rise 7:07 AM
Set 7:15 PM
Waxing Crescent
Rise 7:43 AM
Set 9:32 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 Moderate 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 High 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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