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O'Fallon, MO

93°F
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O'Fallon

Missouri

93°
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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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 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities

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7 PM

91°
RealFeel® 103°
Very Hot
RealFeel Guide
Very Hot
101° to 107°
Caution advised. Danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
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rain drop 8%
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Partly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™103°

Heat Index106°

WindESE 7 mph

Air QualityFair

Max UV Index0.8 (Low)

Wind Gusts10 mph

Humidity66%

Indoor Humidity66% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™4 (Dull)

Cloud Cover33%

Visibility10 mi

Cloud Ceiling33000 ft

8 PM

88°
RealFeel® 99°
Hot
RealFeel Guide
Hot
90° to 100°
Caution advised. Possible danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
LEARN MORE
rain drop 43%
Chevron down
Mostly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™99°

Heat Index101°

WindSE 7 mph

Air QualityFair

Max UV Index0.0 (Low)

Wind Gusts12 mph

Humidity69%

Indoor Humidity69% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover76%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

85°
RealFeel® 93°
Hot
RealFeel Guide
Hot
90° to 100°
Caution advised. Possible danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
LEARN MORE
rain drop 47%
Chevron down
Mostly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

Heat Index94°

WindSE 7 mph

Air QualityFair

Wind Gusts12 mph

Humidity73%

Indoor Humidity73% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover76%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

82°
RealFeel® 86°
Very Warm
RealFeel Guide
Very Warm
82° to 89°
Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.
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rain drop 51%
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Thunderstorms
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

Heat Index88°

WindSE 7 mph

Air QualityFair

Wind Gusts12 mph

Humidity79%

Indoor Humidity79% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover76%

Rain0.04 in

Visibility6 mi

Cloud Ceiling4000 ft

11 PM

81°
RealFeel® 88°
Very Warm
RealFeel Guide
Very Warm
82° to 89°
Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.
LEARN MORE
rain drop 19%
Chevron down
Mostly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

Heat Index86°

WindSE 7 mph

Air QualityFair

Wind Gusts9 mph

Humidity80%

Indoor Humidity80% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover76%

Visibility10 mi

Cloud Ceiling30000 ft

Hourly Weather Forecast for O'Fallon

AccuWeather's hourly forecast for O'Fallon provides hour-by-hour temperatures, RealFeel® Temperature, and precipitation probability through the next 10 days. The current hour shows 91° with a RealFeel® of 103°, partly sunny with a 8% chance of precipitation. Each hourly forecast includes wind speed, humidity, air quality, UV index, and the AccuLumen Brightness Index™, AccuWeather's measure of perceived outdoor light intensity. Forecasts are generated by proprietary systems developed by AccuWeather meteorologists since 1962.

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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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