National Weather Service forecast

O'Fallon, Illinois Weather

55°Overnight: Chance Light Rain
Wind SW 10 mph
7-DayHourlyRadar

O'Fallon 7-Day Forecast

  1. Overnight
    55°F
    Chance Light Rain
    36% chance of precipitation

    A chance of rain before 3am, then a slight chance of drizzle. Mostly cloudy, with a low around 55. Southwest wind around 10 mph, with gusts as high as 22 mph. Chance of precipitation is 40%.

  2. Wednesday
    63°F
    Slight Chance Drizzle then Mostly Cloudy
    11% chance of precipitation

    A slight chance of drizzle before 7am. Mostly cloudy, with a high near 63. West wind 7 to 14 mph.

  3. Wednesday Night
    45°F
    Partly Cloudy

    Partly cloudy, with a low around 45. West wind around 6 mph.

  4. Thursday
    65°F
    Sunny

    Sunny. High near 65, with temperatures falling to around 60 in the afternoon. West wind 6 to 12 mph.

  5. Thursday Night
    47°F
    Partly Cloudy
    2% chance of precipitation

    Partly cloudy, with a low around 47. Northwest wind around 5 mph.

  6. Friday
    57°F
    Partly Sunny
    1% chance of precipitation

    Partly sunny. High near 57, with temperatures falling to around 53 in the afternoon.

  7. Friday Night
    37°F
    Partly Cloudy

    Partly cloudy, with a low around 37.

  8. Saturday
    55°F
    Mostly Sunny

    Mostly sunny, with a high near 55.

  9. Saturday Night
    36°F
    Partly Cloudy

    Partly cloudy, with a low around 36.

  10. Sunday
    60°F
    Sunny
    1% chance of precipitation

    Sunny, with a high near 60.

  11. Sunday Night
    37°F
    Clear

    Clear, with a low around 37.

  12. Monday
    66°F
    Sunny

    Sunny, with a high near 66.

  13. Monday Night
    42°F
    Clear

    Clear, with a low around 42.

  14. Tuesday
    69°F
    Sunny
    1% chance of precipitation

    Sunny, with a high near 69.

Issued by the National Weather Service (LSX office), updated .

O'Fallon Hourly Forecast

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O'Fallon Weather Radar

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About O'Fallon

Population (2020 Census)
32,289
Coordinates
38.597, -89.914
Elevation
551 ft
NWS forecast office
LSX
Time zone
America/Chicago
Sunrise today
6:29 AM CST
Sunset today
4:56 PM CST
Daylight today
10 h 27 min

O'Fallon Weather Questions

What is the weather forecast for O'Fallon, Illinois?

Overnight: A chance of rain before 3am, then a slight chance of drizzle. Mostly cloudy, with a low around 55. Southwest wind around 10 mph, with gusts as high as 22 mph. Chance of precipitation is 40%. Wednesday: A slight chance of drizzle before 7am. Mostly cloudy, with a high near 63. West wind 7 to 14 mph.

Will it rain or snow in O'Fallon this week?

The best chance of precipitation is Overnight at 36%. Periods with a 30% chance or more: Overnight (36%).

How warm and how cold will it get in O'Fallon this week?

The warmest day is Tuesday, with a high near 69°F. The coldest night is Saturday Night, with a low near 36°F.

What time are sunrise and sunset in O'Fallon today?

Sunrise is at 6:29 AM CST and sunset is at 4:56 PM CST, for 10 h 27 min of daylight.

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