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Dangerous heat wave to expand east early this week, affecting 170 million people. Details here Chevron right

O'Fallon, MO

78°F
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O'Fallon

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Winter Center
Today Hourly Daily Radar MinuteCast Monthly Air Quality Health & Activities
Monday, June 23

Day

6/23
98°Hi
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
RealFeel Shade™ 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
Blazing sunshine and very hot; danger of dehydration and heatstroke if outside for extended periods of time
alerts

Extreme Heat Warning

8:00 PM Saturday - 9:00 PM Tuesday

Max UV Index11 (Extreme)

AccuLumen Brightness Index™9 (Very Bright)

WindSSW 9 mph

Wind Gusts17 mph

Probability of Precipitation4%

Probability of Thunderstorms1%

Precipitation0.00 in

Cloud Cover9%

Morning

Afternoon

Night

6/23
76°Lo
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
Mainly clear, warm and humid
alerts

Extreme Heat Warning

8:00 PM Saturday - 9:00 PM Tuesday

WindS 6 mph

Wind Gusts13 mph

Probability of Precipitation12%

Probability of Thunderstorms3%

Precipitation0.00 in

Cloud Cover25%

Evening

Overnight

Sun & Moon

14 hrs 52 mins
Rise 5:37 AM
Set 8:29 PM
Waning Crescent
Rise 3:27 AM
Set 7:12 PM

Temperature History

6/23
High
Low
Forecast
98°
76°
Average
88°
66°
Last Year
95°
71°

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World North America United States Missouri O'Fallon

Weather Near O'Fallon:

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