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O'Fallon, MO

76°F
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O'Fallon

Missouri

76°
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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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May 16 - May 30

Sat 5/16

76° /65°
99%
Rather cloudy with showers and thunderstorms, some heavy; thunderstorms could bring damaging winds, flash flooding and hail

RealFeel®80°

RealFeel Shade™77°

Max UV Index5.0 (Moderate)

WindSSW 7 mph

Hours of Precipitation6

Hours of Rain6

Sun 5/17

91° /71°
5%
Partly sunny and hot; possible danger of dehydration and heatstroke while doing strenuous activities

RealFeel®93°

RealFeel Shade™88°

Max UV Index10.0 (Very High)

WindS 13 mph

Mon 5/18

81° /72°
55%
Not as warm with intervals of clouds and sunshine; breezy in the morning, then becoming humid with a thunderstorm

RealFeel®83°

RealFeel Shade™79°

Max UV Index5.0 (Moderate)

WindS 13 mph

Hours of Precipitation1

Hours of Rain1

Tue 5/19

79° /54°
88%
Considerable cloudiness, breezy and humid with a couple of showers and a thunderstorm; thunderstorms can bring localized damaging wind gusts

RealFeel®81°

RealFeel Shade™79°

Max UV Index3.0 (Moderate)

WindSW 14 mph

Hours of Precipitation3

Hours of Rain3

Wed 5/20

67° /50°
25%
Cooler and less humid with sun and areas of high clouds

RealFeel®68°

RealFeel Shade™64°

Max UV Index4.0 (Moderate)

WindN 10 mph

Thu 5/21

72° /51°
25%
Pleasant with times of clouds and sun

RealFeel®73°

RealFeel Shade™69°

Max UV Index6.0 (High)

WindENE 8 mph

Fri 5/22

78° /56°
7%
Partly sunny and pleasant

RealFeel®84°

RealFeel Shade™76°

Max UV Index11.0 (Extreme)

WindE 5 mph

Sat 5/23

83° /60°
30%
Cloudy with a couple of showers possible

RealFeel®86°

RealFeel Shade™82°

Max UV Index4.0 (Moderate)

WindE 5 mph

Sun 5/24

84° /62°
30%
Mostly cloudy with a thunderstorm possible

RealFeel®91°

RealFeel Shade™86°

Max UV Index9.0 (Very High)

WindWSW 1 mph

Mon 5/25

80° /58°
35%
Mostly cloudy and humid with a couple of showers and thunderstorms possible

RealFeel®87°

RealFeel Shade™82°

Max UV Index8.0 (Very High)

WindS 5 mph

Tue 5/26

81° /60°
0%
Humid with sun and areas of high clouds

RealFeel®90°

RealFeel Shade™86°

Max UV Index6.0 (High)

WindE 9 mph

Wed 5/27

80° /63°
7%
Humid with intervals of clouds and sunshine

RealFeel®91°

RealFeel Shade™84°

Max UV Index10.0 (Very High)

WindESE 8 mph

Thu 5/28

81° /62°
60%
Humid with occasional rain

RealFeel®86°

RealFeel Shade™84°

Max UV Index3.0 (Moderate)

WindSE 7 mph

Hours of Precipitation4

Hours of Rain4

Fri 5/29

79° /58°
25%
Less humid with intervals of clouds and sunshine

RealFeel®86°

RealFeel Shade™77°

Max UV Index7.0 (High)

WindW 7 mph

Sat 5/30

78° /63°
20%
Mostly sunny and humid

RealFeel®89°

RealFeel Shade™81°

Max UV Index11.0 (Extreme)

WindWSW 6 mph

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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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