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O'Fallon, MO

91°F
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O'Fallon

Missouri

91°
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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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7 PM

89°
RealFeel® 100°
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.
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rain drop 14%
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Mostly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Sunday

RealFeel Shade™100°

Heat Index101°

WindSE 6 mph

Air QualityFair

Max UV Index0.7 (Low)

Wind Gusts7 mph

Humidity66%

Indoor Humidity66% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™4 (Dull)

Cloud Cover29%

Visibility10 mi

Cloud Ceiling33400 ft

8 PM

87°
RealFeel® 97°
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 6%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Sunday

Heat Index99°

WindESE 7 mph

Air QualityFair

Wind Gusts8 mph

Humidity74%

Indoor Humidity74% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover19%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

84°
RealFeel® 94°
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 6%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Sunday

Heat Index94°

WindESE 7 mph

Air QualityFair

Wind Gusts7 mph

Humidity80%

Indoor Humidity80% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover13%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

82°
RealFeel® 91°
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 6%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Sunday

Heat Index89°

WindSE 6 mph

Air QualityFair

Wind Gusts7 mph

Humidity83%

Indoor Humidity83% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover15%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

81°
RealFeel® 89°
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 6%
Chevron down
Partly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Sunday

Heat Index87°

WindSE 6 mph

Air QualityFair

Wind Gusts7 mph

Humidity85%

Indoor Humidity85% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover31%

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 89° with a RealFeel® of 100°, mostly sunny with a 14% 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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