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O'Fallon, MO

75°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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May 18 - June 1

Mon 5/18

80° /71°
88%
Clouds and sun with a thunderstorm or two, humid; breezy this morning; thunderstorms can bring hail and damaging winds

RealFeel®83°

RealFeel Shade™80°

Max UV Index5.0 (Moderate)

WindS 13 mph

Hours of Precipitation4

Hours of Rain4

Tue 5/19

77° /54°
88%
Cloudy and humid with a shower and t-storm; breezy in the morning, then not as warm in the afternoon; thunderstorms can bring localized damaging wind gusts

RealFeel®79°

RealFeel Shade™76°

Max UV Index3.0 (Moderate)

WindWSW 12 mph

Hours of Precipitation4

Hours of Rain4

Wed 5/20

67° /50°
12%
Less humid with sun and areas of high clouds

RealFeel®71°

RealFeel Shade™64°

Max UV Index8.0 (Very High)

WindNNE 9 mph

Thu 5/21

72° /59°
25%
Pleasant with times of clouds and sun

RealFeel®77°

RealFeel Shade™69°

Max UV Index6.0 (High)

WindENE 7 mph

Fri 5/22

78° /59°
88%
Cloudy with a couple of showers and a thunderstorm

RealFeel®79°

RealFeel Shade™79°

Max UV Index3.0 (Moderate)

WindENE 5 mph

Hours of Precipitation4

Hours of Rain4

Sat 5/23

79° /60°
30%
Cloudy and humid with a couple of showers possible

RealFeel®82°

RealFeel Shade™78°

Max UV Index4.0 (Moderate)

WindNW 5 mph

Sun 5/24

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

RealFeel®92°

RealFeel Shade™84°

Max UV Index8.0 (Very High)

WindENE 4 mph

Mon 5/25

83° /62°
25%
Humid with intervals of clouds and sun

RealFeel®90°

RealFeel Shade™84°

Max UV Index5.0 (Moderate)

WindE 5 mph

Tue 5/26

81° /63°
64%
Clouds and breaks of sun; humid with a couple of thunderstorms, especially early in the day

RealFeel®92°

RealFeel Shade™84°

Max UV Index7.0 (High)

WindSE 4 mph

Hours of Precipitation2

Hours of Rain2

Wed 5/27

83° /64°
55%
Considerable cloudiness with a little rain; humid

RealFeel®89°

RealFeel Shade™86°

Max UV Index6.0 (High)

WindSE 6 mph

Hours of Precipitation2

Hours of Rain2

Thu 5/28

81° /62°
61%
Humid with occasional rain

RealFeel®88°

RealFeel Shade™84°

Max UV Index5.0 (Moderate)

WindSSE 8 mph

Hours of Precipitation2.5

Hours of Rain2.5

Fri 5/29

80° /59°
80%
Considerable cloudiness with rain tapering off; humid

RealFeel®86°

RealFeel Shade™84°

Max UV Index3.0 (Moderate)

WindSSE 12 mph

Hours of Precipitation4

Hours of Rain4

Sat 5/30

79° /61°
75%
Humid with rain

RealFeel®86°

RealFeel Shade™84°

Max UV Index3.0 (Moderate)

WindS 6 mph

Hours of Precipitation5

Hours of Rain5

Sun 5/31

80° /59°
20%
Partly sunny and humid

RealFeel®92°

RealFeel Shade™83°

Max UV Index11.0 (Extreme)

WindWSW 6 mph

Mon 6/1

84° /63°
25%
Humid with times of clouds and sun

RealFeel®95°

RealFeel Shade™90°

Max UV Index11.0 (Extreme)

WindWNW 8 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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