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O'Fallon, MO

76°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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Hourly

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

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11 AM

82°
RealFeel® 90°
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 59%
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Thunderstorms
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™87°

Heat Index88°

WindSW 7 mph

Air QualityFair

Max UV Index1.7 (Low)

Wind Gusts8 mph

Humidity77%

Indoor Humidity77% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™1 (Dark)

Cloud Cover99%

Visibility10 mi

Cloud Ceiling10000 ft

12 PM

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 49%
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Mostly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™91°

Heat Index93°

WindSW 8 mph

Air QualityFair

Max UV Index5.2 (Moderate)

Wind Gusts9 mph

Humidity68%

Indoor Humidity68% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™3 (Dull)

Cloud Cover86%

Visibility10 mi

Cloud Ceiling30000 ft

1 PM

88°
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 28%
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Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™93°

Heat Index96°

WindSW 8 mph

Air QualityFair

Max UV Index7.7 (Very High)

Wind Gusts9 mph

Humidity62%

Indoor Humidity62% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling30000 ft

2 PM

90°
RealFeel® 104°
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 0%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™96°

Heat Index100°

WindSSW 8 mph

Air QualityPoor

Max UV Index8.0 (Very High)

Wind Gusts9 mph

Humidity58%

Indoor Humidity58% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover42%

Visibility10 mi

Cloud Ceiling30000 ft

3 PM

93°
RealFeel® 105°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™98°

Heat Index102°

WindSSW 8 mph

Air QualityPoor

Max UV Index6.0 (High)

Wind Gusts9 mph

Humidity53%

Indoor Humidity53% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover29%

Visibility10 mi

Cloud Ceiling30000 ft

4 PM

95°
RealFeel® 105°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™100°

Heat Index105°

WindS 8 mph

Air QualityPoor

Max UV Index4.2 (Moderate)

Wind Gusts9 mph

Humidity50%

Indoor Humidity50% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover19%

Visibility10 mi

Cloud Ceiling30000 ft

5 PM

94°
RealFeel® 104°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™100°

Heat Index104°

WindS 7 mph

Air QualityPoor

Max UV Index2.8 (Moderate)

Wind Gusts8 mph

Humidity53%

Indoor Humidity53% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover18%

Visibility10 mi

Cloud Ceiling30000 ft

6 PM

92°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™99°

Heat Index103°

WindSSE 7 mph

Air QualityPoor

Max UV Index1.7 (Low)

Wind Gusts8 mph

Humidity58%

Indoor Humidity58% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover22%

Visibility10 mi

Cloud Ceiling30000 ft

7 PM

90°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

RealFeel Shade™101°

Heat Index102°

WindSE 6 mph

Air QualityPoor

Max UV Index0.7 (Low)

Wind Gusts7 mph

Humidity64%

Indoor Humidity64% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™4 (Dull)

Cloud Cover24%

Visibility10 mi

Cloud Ceiling30000 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 0%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

Heat Index100°

WindESE 7 mph

Air QualityFair

Wind Gusts8 mph

Humidity71%

Indoor Humidity71% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover19%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

85°
RealFeel® 95°
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 0%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

Heat Index95°

WindESE 7 mph

Air QualityFair

Wind Gusts7 mph

Humidity77%

Indoor Humidity77% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover13%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

83°
RealFeel® 92°
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 1%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

Heat Index91°

WindSE 6 mph

Air QualityFair

Wind Gusts7 mph

Humidity81%

Indoor Humidity81% (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.
LEARN MORE
rain drop 2%
Chevron down
Partly cloudy
alerts

Extreme Heat Warning

12:00 PM Sunday - 9:00 PM Saturday

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 82° with a RealFeel® of 90°, thunderstorms with a 59% 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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