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O'Fallon, MO

53°F
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O'Fallon

Missouri

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O'Fallon, MO Weather
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May 2 - May 16

Sat 5/2

60° /41°
55%
Partly sunny and cool with a shower in spots

RealFeel®66°

RealFeel Shade™57°

Max UV Index9.0 (Very High)

WindNNW 8 mph

Sun 5/3

76° /52°
55%
Mostly sunny, becoming breezy in the afternoon with a thunderstorm in spots late

RealFeel®76°

RealFeel Shade™72°

Max UV Index9.0 (Very High)

WindSW 13 mph

Mon 5/4

76° /58°
55%
Intervals of clouds and sunshine; breezy in the morning, then widely separated thunderstorms in the afternoon; thunderstorms can bring hail and damaging winds

RealFeel®80°

RealFeel Shade™73°

Max UV Index9.0 (Very High)

WindSW 12 mph

Tue 5/5

65° /47°
94%
Not as warm with periods of rain and a thunderstorm

RealFeel®64°

RealFeel Shade™61°

Max UV Index2.0 (Low)

WindW 10 mph

Wed 5/6

59° /42°
30%
Cloudy, chance of a little rain; cool

RealFeel®58°

RealFeel Shade™54°

Max UV Index3.0 (Moderate)

WindNNE 10 mph

Thu 5/7

60° /45°
55%
Periods of clouds and sunshine with a shower in spots; cool

RealFeel®61°

RealFeel Shade™57°

Max UV Index6.0 (High)

WindWNW 12 mph

Fri 5/8

66° /49°
25%
Sun and some clouds

RealFeel®69°

RealFeel Shade™63°

Max UV Index6.0 (High)

WindW 9 mph

Sat 5/9

73° /52°
1%
Intervals of clouds and sunshine

RealFeel®79°

RealFeel Shade™71°

Max UV Index10.0 (Very High)

WindNW 5 mph

Sun 5/10

69° /53°
59%
Variable cloudiness with a couple of showers

RealFeel®70°

RealFeel Shade™67°

Max UV Index5.0 (Moderate)

WindSSE 6 mph

Mon 5/11

73° /50°
4%
Clouds yielding to sun

RealFeel®82°

RealFeel Shade™72°

Max UV Index10.0 (Very High)

WindN 1 mph

Tue 5/12

71° /54°
1%
Partly sunny

RealFeel®82°

RealFeel Shade™72°

Max UV Index10.0 (Very High)

WindWSW 4 mph

Wed 5/13

76° /56°
3%
Clouds and sunshine

RealFeel®77°

RealFeel Shade™73°

Max UV Index6.0 (High)

WindS 9 mph

Thu 5/14

77° /53°
85%
Mostly cloudy; morning rain followed by a shower in spots in the afternoon

RealFeel®78°

RealFeel Shade™74°

Max UV Index5.0 (Moderate)

WindSSW 9 mph

Fri 5/15

75° /54°
62%
Cloudy; a couple of showers and a thunderstorm in the morning followed by a little rain in the afternoon

RealFeel®75°

RealFeel Shade™73°

Max UV Index2.0 (Low)

WindNNW 5 mph

Sat 5/16

79° /59°
25%
Cloudy

RealFeel®79°

RealFeel Shade™79°

Max UV Index3.0 (Moderate)

WindS 9 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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