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O'Fallon, MO

96°F
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O'Fallon

Missouri

96°
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O'Fallon, MO Weather
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2 PM

97°
RealFeel® 110°
Dangerous Heat
RealFeel Guide
Dangerous Heat
108° to 115°
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 14%
Chevron down
Partly sunny
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

RealFeel Shade™104°

Heat Index110°

WindWSW 7 mph

Air QualityPoor

Max UV Index5.1 (Moderate)

Wind Gusts10 mph

Humidity48%

Indoor Humidity48% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover45%

Visibility10 mi

Cloud Ceiling33000 ft

3 PM

98°
RealFeel® 108°
Dangerous Heat
RealFeel Guide
Dangerous Heat
108° to 115°
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 14%
Chevron down
Partly sunny
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

RealFeel Shade™103°

Heat Index108°

WindWSW 7 mph

Air QualityPoor

Max UV Index4.2 (Moderate)

Wind Gusts10 mph

Humidity45%

Indoor Humidity45% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

4 PM

95°
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 18%
Chevron down
Partly sunny
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

RealFeel Shade™99°

Heat Index103°

WindWSW 7 mph

Air QualityPoor

Max UV Index3.1 (Moderate)

Wind Gusts8 mph

Humidity46%

Indoor Humidity46% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

5 PM

92°
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 51%
Chevron down
Mostly cloudy w/ t-storms
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

RealFeel Shade™101°

Heat Index106°

WindSW 6 mph

Air QualityPoor

Max UV Index0.7 (Low)

Wind Gusts7 mph

Humidity62%

Indoor Humidity62% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Rain0.08 in

Visibility5 mi

Cloud Ceiling4000 ft

6 PM

89°
RealFeel® 96°
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
Partly sunny
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

RealFeel Shade™94°

Heat Index97°

WindSSW 5 mph

Air QualityFair

Max UV Index1.0 (Low)

Wind Gusts6 mph

Humidity58%

Indoor Humidity58% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

7 PM

86°
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 34%
Chevron down
Partly sunny
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

RealFeel Shade™94°

Heat Index94°

WindSSW 5 mph

Air QualityFair

Max UV Index0.1 (Low)

Wind Gusts5 mph

Humidity66%

Indoor Humidity66% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

8 PM

84°
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 14%
Chevron down
Mostly clear
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

Heat Index92°

WindSW 5 mph

Air QualityFair

Wind Gusts6 mph

Humidity71%

Indoor Humidity71% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover21%

Visibility10 mi

Cloud Ceiling30000 ft

9 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 14%
Chevron down
Mostly clear
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

Heat Index86°

WindWSW 5 mph

Air QualityFair

Wind Gusts5 mph

Humidity78%

Indoor Humidity78% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover24%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

78°
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 14%
Chevron down
Mostly clear
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

WindW 5 mph

Air QualityFair

Wind Gusts5 mph

Humidity85%

Indoor Humidity85% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover25%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

74°
RealFeel® 81°
Pleasant
RealFeel Guide
Pleasant
63° to 81°
Most consider this temperature range ideal.
LEARN MORE
rain drop 14%
Chevron down
Mostly clear
alerts

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

WindW 4 mph

Air QualityFair

Wind Gusts5 mph

Humidity94%

Indoor Humidity94% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover22%

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 97° with a RealFeel® of 110°, partly 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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Weather Near O'Fallon:

  • St. Charles, MO
  • St. Louis, MO
  • St. Peters, MO
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