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Dangerous heat and humidity to grip the Southeast. Chevron right

O'Fallon, IL

87°F
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O'Fallon

Illinois

87°
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O'Fallon, IL Weather
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Today

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 Daily Radar MinuteCast Monthly Air Quality Health & Activities

10 AM

86°
RealFeel® 104°
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

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™95°

WindSSE 4 mph

Air QualityFair

Max UV Index5 (Moderate)

Wind Gusts6 mph

Humidity77%

Indoor Humidity77% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover20%

Visibility10 mi

Cloud Ceiling33000 ft

11 AM

89°
RealFeel® 107°
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
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™98°

WindSW 5 mph

Air QualityFair

Max UV Index7 (High)

Wind Gusts6 mph

Humidity70%

Indoor Humidity70% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™9 (Very Bright)

Cloud Cover30%

Visibility10 mi

Cloud Ceiling30000 ft

12 PM

91°
RealFeel® 109°
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 0%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™99°

WindSSW 6 mph

Air QualityFair

Max UV Index9 (Very High)

Wind Gusts7 mph

Humidity65%

Indoor Humidity65% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover47%

Visibility10 mi

Cloud Ceiling30000 ft

1 PM

93°
RealFeel® 111°
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 1%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™101°

WindSSW 6 mph

Air QualityFair

Max UV Index10 (Very High)

Wind Gusts7 mph

Humidity61%

Indoor Humidity61% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover65%

Visibility10 mi

Cloud Ceiling30000 ft

2 PM

94°
RealFeel® 111°
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 43%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™102°

WindS 6 mph

Air QualityFair

Max UV Index8 (Very High)

Wind Gusts8 mph

Humidity57%

Indoor Humidity57% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™5 (Medium)

Cloud Cover72%

Visibility10 mi

Cloud Ceiling30000 ft

3 PM

93°
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 47%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™101°

WindSSE 6 mph

Air QualityFair

Max UV Index6 (High)

Wind Gusts9 mph

Humidity58%

Indoor Humidity58% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover71%

Visibility10 mi

Cloud Ceiling30000 ft

4 PM

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

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™97°

WindSSE 6 mph

Air QualityFair

Max UV Index2 (Low)

Wind Gusts10 mph

Humidity62%

Indoor Humidity62% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover70%

Rain0.04 in

Visibility6 mi

Cloud Ceiling4000 ft

5 PM

91°
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 18%
Chevron down
Intermittent clouds
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™99°

WindSSE 6 mph

Air QualityFair

Max UV Index3 (Moderate)

Wind Gusts9 mph

Humidity61%

Indoor Humidity61% (Extremely Humid)

Dew Point76° F

AccuLumen Brightness Index™7 (Bright)

Cloud Cover55%

Visibility10 mi

Cloud Ceiling30000 ft

6 PM

90°
RealFeel® 104°
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 14%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™99°

WindSSE 6 mph

Air QualityFair

Max UV Index2 (Low)

Wind Gusts7 mph

Humidity65%

Indoor Humidity65% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover46%

Visibility10 mi

Cloud Ceiling30000 ft

7 PM

89°
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 11%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™98°

WindSSE 5 mph

Air QualityFair

Max UV Index1 (Low)

Wind Gusts6 mph

Humidity69%

Indoor Humidity69% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™6 (Medium)

Cloud Cover42%

Visibility10 mi

Cloud Ceiling30000 ft

8 PM

85°
RealFeel® 97°
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 5%
Chevron down
Partly sunny
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

RealFeel Shade™97°

WindSE 5 mph

Air QualityFair

Max UV Index0 (Low)

Wind Gusts10 mph

Humidity78%

Indoor Humidity78% (Dangerously Humid)

Dew Point78° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover35%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

82°
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 5%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

WindSE 5 mph

Air QualityFair

Wind Gusts10 mph

Humidity85%

Indoor Humidity85% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover28%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

79°
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 5%
Chevron down
Mostly clear
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

WindSSE 5 mph

Air QualityFair

Wind Gusts12 mph

Humidity92%

Indoor Humidity92% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover26%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

77°
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 5%
Chevron down
Partly cloudy
alerts

Extreme Heat Warning

12:00 PM Saturday - 7:00 PM Tuesday

WindSSE 5 mph

Air QualityFair

Wind Gusts10 mph

Humidity97%

Indoor Humidity95% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover45%

Visibility10 mi

Cloud Ceiling30000 ft

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Weather Near O'Fallon:

  • O'Fallon, MO
  • St. Charles, MO
  • St. Louis, MO
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