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O'Fallon, MO

89°F
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O'Fallon, MO Weather
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Winter Center
Today Hourly Daily Radar MinuteCast® Monthly Air Quality Health & Activities
Wednesday, September 17

Current Weather

5:48 PM

89°F
Sunny
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
RealFeel Shade™ 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
RealFeel®
90°
RealFeel Shade™
88°
Max UV Index
1.0 (Low)
Wind
NNE 2 mph
Wind Gusts
3 mph
Humidity
32%
Indoor Humidity
32% (Slightly Humid)
Dew Point
56° F
Pressure
↔ 29.94 in
Cloud Cover
5%
Visibility
37 mi
Cloud Ceiling
40000 ft

Day

9/17
91°Hi
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
RealFeel Shade™ 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.
LEARN MORE
Hot with brilliant sunshine; air quality will be unhealthy for sensitive groups
alerts

Air Quality Alert

3:10 PM Friday - 8:00 PM Thursday

Max UV Index6.0 (High)

AccuLumen Brightness Index™10 (Very Bright)

WindENE 4 mph

Wind Gusts8 mph

Probability of Precipitation1%

Probability of Thunderstorms0%

Precipitation0.00 in

Cloud Cover3%

Morning

Afternoon

Night

9/17
57°Lo
RealFeel® 57°
Cool
RealFeel Guide
Cool
53° to 62°
Light jacket or sweater may be appropriate.
LEARN MORE
Mostly clear
alerts

Air Quality Alert

3:10 PM Friday - 8:00 PM Thursday

WindE 4 mph

Wind Gusts9 mph

Probability of Precipitation0%

Probability of Thunderstorms0%

Precipitation0.00 in

Cloud Cover11%

Evening

Overnight

Sun & Moon

12 hrs 22 mins
Rise 6:46 AM
Set 7:08 PM
Waning Crescent
Rise 2:11 AM
Set 5:17 PM

Temperature History

9/17
High
Low
Forecast
91°
57°
Average
80°
55°
Last Year
87°
57°

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World North America United States Missouri O'Fallon

Weather Near O'Fallon:

  • St. Charles, MO
  • St. Louis, MO
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