National Weather Service forecast

O'Fallon, Missouri Weather

54°Overnight: Slight Chance Drizzle
Wind SW 9 mph
7-DayHourlyRadar

O'Fallon 7-Day Forecast

  1. Overnight
    54°F
    Slight Chance Drizzle
    13% chance of precipitation

    A slight chance of drizzle. Mostly cloudy, with a low around 54. Southwest wind around 9 mph, with gusts as high as 22 mph.

  2. Wednesday
    59°F
    Slight Chance Drizzle then Mostly Cloudy
    12% chance of precipitation

    A slight chance of drizzle before noon. Mostly cloudy, with a high near 59. West wind 7 to 13 mph, with gusts as high as 21 mph.

  3. Wednesday Night
    43°F
    Partly Cloudy

    Partly cloudy, with a low around 43. West wind around 6 mph.

  4. Thursday
    63°F
    Sunny

    Sunny. High near 63, with temperatures falling to around 58 in the afternoon. West wind 5 to 10 mph.

  5. Thursday Night
    44°F
    Mostly Cloudy
    3% chance of precipitation

    Mostly cloudy, with a low around 44. Northwest wind around 6 mph.

  6. Friday
    56°F
    Partly Sunny
    4% chance of precipitation

    Partly sunny. High near 56, with temperatures falling to around 52 in the afternoon.

  7. Friday Night
    35°F
    Partly Cloudy

    Partly cloudy, with a low around 35.

  8. Saturday
    54°F
    Mostly Sunny

    Mostly sunny, with a high near 54.

  9. Saturday Night
    34°F
    Partly Cloudy

    Partly cloudy, with a low around 34.

  10. Sunday
    61°F
    Sunny
    1% chance of precipitation

    Sunny, with a high near 61.

  11. Sunday Night
    35°F
    Clear

    Clear, with a low around 35.

  12. Monday
    65°F
    Sunny

    Sunny, with a high near 65.

  13. Monday Night
    40°F
    Clear

    Clear, with a low around 40.

  14. Tuesday
    68°F
    Sunny
    1% chance of precipitation

    Sunny, with a high near 68.

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)
91,316
Coordinates
38.783, -90.715
Elevation
535 ft
NWS forecast office
LSX
Time zone
America/Chicago
Sunrise today
6:33 AM CST
Sunset today
4:59 PM CST
Daylight today
10 h 27 min

O'Fallon Weather Questions

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

Overnight: A slight chance of drizzle. Mostly cloudy, with a low around 54. Southwest wind around 9 mph, with gusts as high as 22 mph. Wednesday: A slight chance of drizzle before noon. Mostly cloudy, with a high near 59. West wind 7 to 13 mph, with gusts as high as 21 mph.

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

Not much. The highest chance of precipitation in the 7-day forecast is 13%, Overnight.

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

The warmest day is Tuesday, with a high near 68°F. The coldest night is Saturday Night, with a low near 34°F.

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

Sunrise is at 6:33 AM CST and sunset is at 4:59 PM CST, for 10 h 27 min of daylight.

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