O'Fallon, IL Weather Forecast

Today's Weather

Tue, Sep 15

Mostly sunny with record-tying temperatures; a thunderstorm late this afternoon; danger of dehydration and heatstroke if outside for extended periods of time Hi: 100°

Tonight: Partly cloudy, very warm and very humid Lo: 73°

Current Weather

12:08 PM

Air Quality Unhealthy

O'Fallon Weather Radar

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Clouds

Temperature

Hourly Weather

10-Day Weather Forecast

Today

9/15

100° 73°

Very hot

Night: Partly cloudy, warm and humid

55%

Wed

9/16

98° 72°

Very hot

A thunderstorm around early

55%

Thu

9/17

98° 72°

A thunderstorm in spots

Mainly clear and very warm

55%

Fri

9/18

98° 69°

A thunderstorm in spots

Partly cloudy, warm and humid

55%

Sat

9/19

98° 69°

Very hot

Mainly clear, warm and humid

12%

Sun

9/20

94° 70°

Mostly sunny and hot

Partly cloudy, warm and humid

19%

Mon

9/21

83° 64°

A t-storm or two; not as hot

Partly cloudy and humid

63%

Tue

9/22

80° 59°

Partly sunny and less humid

Clear

Wed

9/23

81° 58°

Sun and clouds

Partly cloudy

Thu

9/24

81° 58°

Mostly sunny

Mostly cloudy

23%

Sun & Moon

12 hrs 27 mins

Rise 6:41 AM

Set 7:08 PM

Waxing Crescent

Rise 11:32 AM

Set 9:13 PM

Air Quality

Air Quality Unhealthy

Health effects can be immediately felt by sensitive groups. Healthy individuals may experience difficulty breathing and throat irritation with prolonged exposure. Limit outdoor activity.