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O'Fallon, MO

99°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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Winter Center

Today

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

Today's Weather

Tue, Sep 1

Very hot with blazing sunshine; caution advised if outside for extended periods of time Hi: 100°

Tonight: Clear, warm and humid Lo: 73°

Current Weather

1:37 PM

99°F
RealFeel® 112°
Sunny More Details
RealFeel Shade™ 103°
Heat Index 105°
Wind W 2 mph
Wind Gusts 4 mph
Air Quality Poor

Looking Ahead

Sweltering late-season heat and humidity expected this week; stay hydrated

O'Fallon Weather Radar

O'Fallon Weather Radar
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Clouds
Temperature

Hourly Weather

2 PM 99°
rain drop 0%
3 PM 100°
rain drop 0%
4 PM 98°
rain drop 0%
5 PM 97°
rain drop 0%
6 PM 95°
rain drop 0%
7 PM 91°
rain drop 0%
8 PM 88°
rain drop 0%
9 PM 85°
rain drop 0%
10 PM 82°
rain drop 0%
11 PM 79°
rain drop 0%
12 AM 78°
rain drop 0%
1 AM 77°
rain drop 0%

10-Day Weather Forecast

Today

9/1

100° 73°

Very hot with sunshine

Night: Clear, warm and humid
1%

Wed

9/2

99° 73°

Mostly sunny and very hot

Clear, warm and humid
8%

Thu

9/3

100° 74°

Sunshine and sweltering heat

Clear, warm and humid
8%

Fri

9/4

98° 72°

Mostly sunny and very hot

Mainly clear, warm and humid
9%

Sat

9/5

96° 71°

Partly sunny and very hot

Mainly clear, warm and humid
25%

Sun

9/6

96° 69°

Very hot with a stray t-storm

Partly cloudy and humid
55%

Mon

9/7

92° 70°

Hot and humid with sunshine

Clouds breaking; warm
23%

Tue

9/8

89° 66°

High clouds; warm, less humid

Clear to partly cloudy
1%

Wed

9/9

90° 68°

Hot with plenty of sun

Clear
1%

Thu

9/10

86° 64°

Sunny and remaining very warm

Clear
2%

Sun & Moon

13 hrs 01 mins
Rise 6:32 AM
Set 7:33 PM
Waning Gibbous
Rise 9:38 PM
Set 12:34 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 Very High 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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