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Days of storms, flood risk expected from Plains to mid-Atlantic. Click for details. Chevron right

O'Fallon, MO

94°F
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O'Fallon

Missouri

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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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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 6%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

RealFeel Shade™101°

Heat Index107°

WindSW 10 mph

Air QualityFair

Max UV Index4.3 (Moderate)

Wind Gusts22 mph

Humidity51%

Indoor Humidity51% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

5 PM

94°
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 6%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

RealFeel Shade™99°

Heat Index104°

WindSW 10 mph

Air QualityFair

Max UV Index2.8 (Moderate)

Wind Gusts17 mph

Humidity52%

Indoor Humidity52% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

6 PM

92°
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 6%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

RealFeel Shade™98°

Heat Index102°

WindSW 8 mph

Air QualityFair

Max UV Index1.8 (Low)

Wind Gusts14 mph

Humidity57%

Indoor Humidity57% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

7 PM

89°
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 4%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

RealFeel Shade™98°

Heat Index100°

WindSW 7 mph

Air QualityFair

Max UV Index0.8 (Low)

Wind Gusts12 mph

Humidity63%

Indoor Humidity63% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™4 (Dull)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

8 PM

86°
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 0%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

RealFeel Shade™92°

Heat Index94°

WindSSW 7 mph

Air QualityFair

Max UV Index0.0 (Low)

Wind Gusts10 mph

Humidity66%

Indoor Humidity66% (Extremely Humid)

Dew Point74° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover37%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

83°
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 0%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

Heat Index89°

WindSSW 7 mph

Air QualityFair

Wind Gusts9 mph

Humidity72%

Indoor Humidity72% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover55%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

80°
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.
LEARN MORE
rain drop 0%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

Heat Index84°

WindSSW 7 mph

Air QualityFair

Wind Gusts7 mph

Humidity78%

Indoor Humidity78% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover65%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

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

Extreme Heat Warning

12:00 PM Sunday - 8:00 PM Wednesday

WindSSW 7 mph

Air QualityFair

Wind Gusts7 mph

Humidity86%

Indoor Humidity86% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover58%

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 95° with a RealFeel® of 105°, partly sunny with a 6% 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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