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O'Fallon, IL

81°F
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O'Fallon

Illinois

81°
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O'Fallon, IL Weather
Today WinterCast Local {stormName} Tracker Hourly 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities

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11 AM

81°
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 7%
Chevron down
Intermittent clouds

RealFeel Shade™84°

Heat Index85°

WindN 8 mph

Air QualityFair

Max UV Index5.8 (High)

Wind Gusts9 mph

Humidity72%

Indoor Humidity72% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover51%

Visibility10 mi

Cloud Ceiling13100 ft

12 PM

81°
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 7%
Chevron down
Intermittent clouds

RealFeel Shade™84°

Heat Index86°

WindN 8 mph

Air QualityFair

Max UV Index4.6 (Moderate)

Wind Gusts10 mph

Humidity70%

Indoor Humidity70% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling4000 ft

1 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 9%
Chevron down
Intermittent clouds

RealFeel Shade™85°

Heat Index87°

WindN 8 mph

Air QualityFair

Max UV Index5.7 (High)

Wind Gusts13 mph

Humidity66%

Indoor Humidity66% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling7100 ft

2 PM

83°
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 14%
Chevron down
Intermittent clouds

RealFeel Shade™85°

Heat Index87°

WindN 8 mph

Air QualityFair

Max UV Index5.1 (Moderate)

Wind Gusts13 mph

Humidity65%

Indoor Humidity65% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling7100 ft

3 PM

83°
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 14%
Chevron down
Intermittent clouds

RealFeel Shade™85°

Heat Index87°

WindNNE 8 mph

Air QualityFair

Max UV Index3.8 (Moderate)

Wind Gusts13 mph

Humidity67%

Indoor Humidity67% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling7100 ft

4 PM

84°
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 18%
Chevron down
Intermittent clouds

RealFeel Shade™87°

Heat Index88°

WindNNE 8 mph

Air QualityFair

Max UV Index2.5 (Low)

Wind Gusts14 mph

Humidity65%

Indoor Humidity65% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling7100 ft

5 PM

80°
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 51%
Chevron down
Mostly cloudy w/ t-storms

RealFeel Shade™82°

Heat Index84°

WindNE 8 mph

Air QualityFair

Max UV Index1.3 (Low)

Wind Gusts12 mph

Humidity79%

Indoor Humidity79% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Rain0.08 in

Visibility5 mi

Cloud Ceiling4000 ft

6 PM

80°
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.
LEARN MORE
rain drop 47%
Chevron down
Intermittent clouds

RealFeel Shade™84°

Heat Index84°

WindNE 7 mph

Air QualityFair

Max UV Index1.6 (Low)

Wind Gusts10 mph

Humidity73%

Indoor Humidity73% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling22400 ft

7 PM

80°
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.
LEARN MORE
rain drop 30%
Chevron down
Intermittent clouds

RealFeel Shade™84°

Heat Index84°

WindNE 6 mph

Air QualityFair

Max UV Index1.0 (Low)

Wind Gusts8 mph

Humidity74%

Indoor Humidity74% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™4 (Dull)

Cloud Cover70%

Visibility10 mi

Cloud Ceiling30000 ft

8 PM

78°
RealFeel® 83°
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
Mostly sunny

RealFeel Shade™83°

WindNE 6 mph

Air QualityFair

Max UV Index0.2 (Low)

Wind Gusts6 mph

Humidity80%

Indoor Humidity80% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover25%

Visibility10 mi

Cloud Ceiling30000 ft

9 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 2%
Chevron down
Mostly clear

WindNE 5 mph

Air QualityFair

Wind Gusts6 mph

Humidity84%

Indoor Humidity84% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover25%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

75°
RealFeel® 80°
Pleasant
RealFeel Guide
Pleasant
63° to 81°
Most consider this temperature range ideal.
LEARN MORE
rain drop 2%
Chevron down
Mostly clear

WindNE 5 mph

Air QualityFair

Wind Gusts5 mph

Humidity89%

Indoor Humidity89% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover19%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

73°
RealFeel® 78°
Pleasant
RealFeel Guide
Pleasant
63° to 81°
Most consider this temperature range ideal.
LEARN MORE
rain drop 2%
Chevron down
Mostly clear

WindENE 5 mph

Air QualityFair

Wind Gusts5 mph

Humidity93%

Indoor Humidity93% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover11%

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 81° with a RealFeel® of 91°, intermittent clouds with a 7% 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:

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  • St. Charles, MO
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