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O'Fallon, MO

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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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11 AM

83°

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.

32%

Cloudy

RealFeel Shade™84°

Heat Index87°

WindSSE 8 mph

Air QualityFair

Max UV Index3.8 (Moderate)

Wind Gusts12 mph

Humidity63%

Indoor Humidity63% (Very Humid)

Dew Point69° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling21400 ft

12 PM

85°

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.

32%

Cloudy

RealFeel Shade™85°

Heat Index88°

WindSE 9 mph

Air QualityFair

Max UV Index4.7 (Moderate)

Wind Gusts14 mph

Humidity58%

Indoor Humidity58% (Very Humid)

Dew Point68° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling18000 ft

1 PM

86°

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.

32%

Cloudy

RealFeel Shade™86°

Heat Index89°

WindSE 9 mph

Air QualityFair

Max UV Index4.8 (Moderate)

Wind Gusts17 mph

Humidity54%

Indoor Humidity54% (Very Humid)

Dew Point68° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling14700 ft

2 PM

87°

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.

34%

Cloudy

RealFeel Shade™86°

Heat Index89°

WindSE 9 mph

Air QualityFair

Max UV Index4.3 (Moderate)

Wind Gusts17 mph

Humidity53%

Indoor Humidity53% (Very Humid)

Dew Point67° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling14700 ft

3 PM

87°

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.

34%

Cloudy

RealFeel Shade™87°

Heat Index91°

WindSE 10 mph

Air QualityFair

Max UV Index3.3 (Moderate)

Wind Gusts18 mph

Humidity51%

Indoor Humidity51% (Very Humid)

Dew Point68° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling14700 ft

4 PM

86°

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.

40%

Cloudy

RealFeel Shade™86°

Heat Index89°

WindSE 9 mph

Air QualityFair

Max UV Index2.1 (Low)

Wind Gusts20 mph

Humidity54%

Indoor Humidity54% (Very Humid)

Dew Point68° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling14700 ft

5 PM

84°

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.

51%

Thunderstorms

RealFeel Shade™83°

Heat Index88°

WindSE 9 mph

Air QualityFair

Max UV Index0.9 (Low)

Wind Gusts17 mph

Humidity62%

Indoor Humidity62% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Rain0.05 in

Visibility5 mi

Cloud Ceiling4000 ft

6 PM

83°

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.

47%

Cloudy

RealFeel Shade™86°

Heat Index87°

WindSE 8 mph

Air QualityFair

Max UV Index0.9 (Low)

Wind Gusts15 mph

Humidity65%

Indoor Humidity65% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling14700 ft

7 PM

82°

RealFeel® 85°

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.

44%

Cloudy

RealFeel Shade™85°

Heat Index86°

WindSE 8 mph

Air QualityFair

Max UV Index0.5 (Low)

Wind Gusts13 mph

Humidity67%

Indoor Humidity67% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover90%

Visibility10 mi

Cloud Ceiling14700 ft

8 PM

78°

RealFeel® 81°

Pleasant

RealFeel Guide

Pleasant

63° to 81°

Most consider this temperature range ideal.

46%

Cloudy

RealFeel Shade™81°

WindSE 7 mph

Air QualityFair

Max UV Index0.1 (Low)

Wind Gusts13 mph

Humidity76%

Indoor Humidity76% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover94%

Visibility10 mi

Cloud Ceiling12100 ft

9 PM

77°

RealFeel® 80°

Pleasant

RealFeel Guide

Pleasant

63° to 81°

Most consider this temperature range ideal.

49%

Cloudy

WindSE 6 mph

Air QualityFair

Wind Gusts12 mph

Humidity81%

Indoor Humidity81% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover94%

Visibility10 mi

Cloud Ceiling9600 ft

10 PM

74°

RealFeel® 75°

Pleasant

RealFeel Guide

Pleasant

63° to 81°

Most consider this temperature range ideal.

54%

Thunderstorms

WindSSE 6 mph

Air QualityFair

Wind Gusts10 mph

Humidity89%

Indoor Humidity89% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover94%

Rain0.05 in

Visibility5 mi

Cloud Ceiling4000 ft

11 PM

74°

RealFeel® 77°

Pleasant

RealFeel Guide

Pleasant

63° to 81°

Most consider this temperature range ideal.

45%

Thunderstorms

WindSSE 6 mph

Air QualityFair

Wind Gusts10 mph

Humidity89%

Indoor Humidity89% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover94%

Visibility10 mi

Cloud Ceiling4000 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 83° with a RealFeel® of 89°, cloudy 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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