National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Sparta, Sparta / Fort McCoy Airport (KCMY)

Lat: 43.96°NLon: 90.74°WElev: 837ft.

Overcast

37°F

3°C

Humidity 60%
Wind Speed Calm
Barometer 30.12 in (1021.2 mb)
Dewpoint 25°F (-4°C)
Visibility 10.00 mi
Last update 12 Nov 6:55 pm CST
Extended Forecast for

Ontario WI

  • Tonight

    Tonight: Cloudy, then gradually becoming partly cloudy, with a low around 23. North wind 5 to 8 mph, with gusts as high as 18 mph.

    Low: 23 °F

    Decreasing
    Clouds

  • Friday

    Friday: Partly sunny, with a high near 42. North wind 5 to 10 mph becoming light in the afternoon. Winds could gust as high as 18 mph.

    High: 42 °F

    Partly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 21. Calm wind.

    Low: 21 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, then gradually becoming sunny, with a high near 46. Calm wind.

    High: 46 °F

    Becoming
    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 23. Calm wind.

    Low: 23 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 48. Calm wind.

    High: 48 °F

    Sunny

  • Sunday Night

    Sunday Night: Clear, with a low around 24. Calm wind.

    Low: 24 °F

    Clear

  • Monday

    Monday: Sunny, with a high near 52. Calm wind becoming southwest around 6 mph.

    High: 52 °F

    Sunny

  • Monday Night

    Monday Night: Clear, with a low around 25. Calm wind.

    Low: 25 °F

    Clear

Detailed Forecast

Tonight
Cloudy, then gradually becoming partly cloudy, with a low around 23. North wind 5 to 8 mph, with gusts as high as 18 mph.
Friday
Partly sunny, with a high near 42. North wind 5 to 10 mph becoming light in the afternoon. Winds could gust as high as 18 mph.
Friday Night
Partly cloudy, with a low around 21. Calm wind.
Saturday
Partly sunny, then gradually becoming sunny, with a high near 46. Calm wind.
Saturday Night
Clear, with a low around 23. Calm wind.
Sunday
Sunny, with a high near 48. Calm wind.
Sunday Night
Clear, with a low around 24. Calm wind.
Monday
Sunny, with a high near 52. Calm wind becoming southwest around 6 mph.
Monday Night
Clear, with a low around 25. Calm wind.
Tuesday
Sunny, with a high near 56. Calm wind becoming south 5 to 8 mph in the morning.
Tuesday Night
Partly cloudy, with a low around 32. South wind 3 to 5 mph. Winds could gust as high as 18 mph.
Wednesday
Mostly sunny, with a high near 57. Light south wind increasing to 5 to 10 mph in the morning. Winds could gust as high as 21 mph.
Wednesday Night
A 20 percent chance of rain. Mostly cloudy, with a low around 40. South wind 3 to 5 mph. Winds could gust as high as 20 mph.
Thursday
A 40 percent chance of rain. Mostly cloudy, with a high near 59. Light south wind becoming southwest 5 to 9 mph in the morning. Winds could gust as high as 20 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Ontario WI
 43.71°N 90.58°W
Last Update:
3:56 pm CST Nov 12, 2026
Forecast Valid:
7pm CST Nov 12, 2026-6pm CST Nov 19, 2026
 
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Additional Resources

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Chance of Precipitation