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O'Fallon, MO

83°F
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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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Today

Hourly

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

View hourly forecasts 10-days ahead

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11 AM

85°
RealFeel® 98°
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 32%
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Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™92°

Heat Index94°

WindWSW 7 mph

Air QualityFair

Max UV Index4.5 (Moderate)

Wind Gusts8 mph

Humidity74%

Indoor Humidity74% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™5 (Medium)

Cloud Cover74%

Visibility10 mi

Cloud Ceiling25900 ft

12 PM

87°
RealFeel® 101°
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.
LEARN MORE
rain drop 32%
Chevron down
Cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™95°

Heat Index98°

WindWSW 7 mph

Air QualityFair

Max UV Index4.2 (Moderate)

Wind Gusts9 mph

Humidity71%

Indoor Humidity71% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™1 (Dark)

Cloud Cover95%

Visibility10 mi

Cloud Ceiling28000 ft

1 PM

89°
RealFeel® 102°
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.
LEARN MORE
rain drop 28%
Chevron down
Cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™96°

Heat Index100°

WindSW 8 mph

Air QualityFair

Max UV Index4.8 (Moderate)

Wind Gusts9 mph

Humidity64%

Indoor Humidity64% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™1 (Dark)

Cloud Cover95%

Visibility10 mi

Cloud Ceiling30000 ft

2 PM

91°
RealFeel® 106°
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.
LEARN MORE
rain drop 20%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™98°

Heat Index102°

WindSW 7 mph

Air QualityFair

Max UV Index7.0 (High)

Wind Gusts9 mph

Humidity60%

Indoor Humidity60% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling30000 ft

3 PM

93°
RealFeel® 106°
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.
LEARN MORE
rain drop 20%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™100°

Heat Index104°

WindS 7 mph

Air QualityFair

Max UV Index5.2 (Moderate)

Wind Gusts9 mph

Humidity56%

Indoor Humidity56% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling30000 ft

4 PM

92°
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.
LEARN MORE
rain drop 20%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™99°

Heat Index104°

WindSE 7 mph

Air QualityFair

Max UV Index2.0 (Low)

Wind Gusts10 mph

Humidity59%

Indoor Humidity59% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling4000 ft

5 PM

91°
RealFeel® 101°
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.
LEARN MORE
rain drop 20%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™97°

Heat Index102°

WindESE 7 mph

Air QualityFair

Max UV Index2.4 (Low)

Wind Gusts10 mph

Humidity60%

Indoor Humidity60% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling30000 ft

6 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.
LEARN MORE
rain drop 20%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™97°

Heat Index101°

WindESE 7 mph

Air QualityFair

Max UV Index1.5 (Low)

Wind Gusts10 mph

Humidity64%

Indoor Humidity64% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling30000 ft

7 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 25%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™97°

Heat Index98°

WindESE 7 mph

Air QualityFair

Max UV Index0.8 (Low)

Wind Gusts10 mph

Humidity72%

Indoor Humidity72% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™4 (Dull)

Cloud Cover56%

Visibility10 mi

Cloud Ceiling30000 ft

8 PM

83°
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 43%
Chevron down
Mostly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™93°

Heat Index92°

WindSE 7 mph

Air QualityFair

Max UV Index0.0 (Low)

Wind Gusts12 mph

Humidity81%

Indoor Humidity81% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover76%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

80°
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.
LEARN MORE
rain drop 47%
Chevron down
Mostly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

Heat Index86°

WindSE 7 mph

Air QualityFair

Wind Gusts12 mph

Humidity87%

Indoor Humidity87% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover76%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

77°
RealFeel® 82°
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 51%
Chevron down
Thunderstorms
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

WindSE 7 mph

Air QualityFair

Wind Gusts12 mph

Humidity93%

Indoor Humidity93% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover76%

Rain0.04 in

Visibility6 mi

Cloud Ceiling4000 ft

11 PM

77°
RealFeel® 84°
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

WindSE 7 mph

Air QualityFair

Wind Gusts9 mph

Humidity92%

Indoor Humidity92% (Extremely Humid)

Dew Point75° 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 85° with a RealFeel® of 98°, intermittent clouds with a 32% 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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