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O'Fallon, MO

79°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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6 AM

77°
RealFeel® 81°
Pleasant
RealFeel Guide
Pleasant
63° to 81°
Most consider this temperature range ideal.
LEARN MORE
rain drop 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

WindSSW 6 mph

Air QualityFair

Wind Gusts6 mph

Humidity81%

Indoor Humidity81% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover0%

Visibility10 mi

Cloud Ceiling30000 ft

7 AM

76°
RealFeel® 80°
Pleasant
RealFeel Guide
Pleasant
63° to 81°
Most consider this temperature range ideal.
LEARN MORE
rain drop 0%
Chevron down
Sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™80°

WindSW 6 mph

Air QualityFair

Max UV Index0.4 (Low)

Wind Gusts6 mph

Humidity84%

Indoor Humidity84% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover0%

Visibility10 mi

Cloud Ceiling30000 ft

8 AM

79°
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 0%
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Sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™82°

Heat Index80°

WindSW 6 mph

Air QualityFair

Max UV Index1.3 (Low)

Wind Gusts7 mph

Humidity76%

Indoor Humidity76% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover0%

Visibility10 mi

Cloud Ceiling30000 ft

9 AM

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 0%
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Sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™87°

Heat Index88°

WindSW 7 mph

Air QualityFair

Max UV Index2.3 (Low)

Wind Gusts9 mph

Humidity69%

Indoor Humidity69% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™10 (Very Bright)

Cloud Cover0%

Visibility10 mi

Cloud Ceiling30000 ft

10 AM

87°
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 0%
Chevron down
Sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™92°

Heat Index94°

WindSW 8 mph

Air QualityFair

Max UV Index3.6 (Moderate)

Wind Gusts13 mph

Humidity61%

Indoor Humidity61% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™10 (Very Bright)

Cloud Cover0%

Visibility10 mi

Cloud Ceiling30000 ft

11 AM

91°
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 0%
Chevron down
Sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™95°

Heat Index98°

WindSW 8 mph

Air QualityFair

Max UV Index4.8 (Moderate)

Wind Gusts13 mph

Humidity55%

Indoor Humidity55% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover6%

Visibility10 mi

Cloud Ceiling30000 ft

12 PM

93°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™96°

Heat Index100°

WindSW 8 mph

Air QualityFair

Max UV Index6.4 (High)

Wind Gusts14 mph

Humidity49%

Indoor Humidity49% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover13%

Visibility10 mi

Cloud Ceiling30000 ft

1 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

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™98°

Heat Index102°

WindSW 8 mph

Air QualityFair

Max UV Index7.1 (High)

Wind Gusts13 mph

Humidity45%

Indoor Humidity45% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover19%

Visibility10 mi

Cloud Ceiling30000 ft

2 PM

97°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™99°

Heat Index104°

WindSSW 8 mph

Air QualityFair

Max UV Index6.4 (High)

Wind Gusts14 mph

Humidity42%

Indoor Humidity42% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover18%

Visibility10 mi

Cloud Ceiling30000 ft

3 PM

99°
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

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™101°

Heat Index106°

WindSSW 8 mph

Air QualityFair

Max UV Index4.8 (Moderate)

Wind Gusts14 mph

Humidity39%

Indoor Humidity39% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover15%

Visibility10 mi

Cloud Ceiling30000 ft

4 PM

97°
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 0%
Chevron down
Mostly sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™99°

Heat Index103°

WindSSW 8 mph

Air QualityFair

Max UV Index3.6 (Moderate)

Wind Gusts15 mph

Humidity40%

Indoor Humidity40% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover11%

Visibility10 mi

Cloud Ceiling30000 ft

5 PM

96°
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

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™98°

Heat Index102°

WindS 7 mph

Air QualityFair

Max UV Index2.3 (Low)

Wind Gusts12 mph

Humidity42%

Indoor Humidity42% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover10%

Visibility10 mi

Cloud Ceiling30000 ft

6 PM

94°
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
Sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™97°

Heat Index100°

WindS 7 mph

Air QualityFair

Max UV Index1.3 (Low)

Wind Gusts9 mph

Humidity47%

Indoor Humidity47% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover9%

Visibility10 mi

Cloud Ceiling30000 ft

7 PM

92°
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 0%
Chevron down
Sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™96°

Heat Index99°

WindS 6 mph

Air QualityFair

Max UV Index0.4 (Low)

Wind Gusts7 mph

Humidity52%

Indoor Humidity52% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover8%

Visibility10 mi

Cloud Ceiling30000 ft

8 PM

89°
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 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index96°

WindSSE 6 mph

Air QualityFair

Wind Gusts9 mph

Humidity58%

Indoor Humidity58% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover5%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

86°
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 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index92°

WindS 6 mph

Air QualityFair

Wind Gusts8 mph

Humidity63%

Indoor Humidity63% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover2%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

83°
RealFeel® 87°
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 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index87°

WindS 6 mph

Air QualityFair

Wind Gusts7 mph

Humidity69%

Indoor Humidity69% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover1%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

82°
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 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index87°

WindS 6 mph

Air QualityFair

Wind Gusts7 mph

Humidity70%

Indoor Humidity70% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover4%

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 77° with a RealFeel® of 81°, clear with a 0% 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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