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.

Fair

62°F

17°C

Humidity 76%
Wind Speed Calm
Barometer 29.89 in (1012.6 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Last update 7 Oct 9:55 am CDT
Extended Forecast for

Ontario WI

  • Today

    Today: Sunny, with a high near 75. Northwest wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 75 °F

    Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 45. West wind 5 to 8 mph becoming calm in the evening.

    Low: 45 °F

    Increasing
    Clouds

  • Thursday

    Thursday: Increasing clouds, with a high near 67. Calm wind becoming northwest 5 to 7 mph in the afternoon.

    High: 67 °F

    Increasing
    Clouds

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 43. Calm wind.

    Low: 43 °F

    Partly Cloudy

  • Friday

    Friday: A 20 percent chance of showers before 1pm. Mostly sunny, with a high near 72. Light and variable wind becoming south 5 to 10 mph in the afternoon. Winds could gust as high as 18 mph.

    High: 72 °F

    Slight Chance
    Showers

  • Friday Night

    Friday Night: Mostly clear, with a low around 56. South wind around 6 mph, with gusts as high as 22 mph.

    Low: 56 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 81. Breezy, with a south wind 9 to 17 mph, with gusts as high as 28 mph.

    High: 81 °F

    Sunny then
    Sunny and
    Breezy

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 60. South wind 7 to 13 mph, with gusts as high as 28 mph.

    Low: 60 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 80. South wind 5 to 9 mph, with gusts as high as 18 mph.

    High: 80 °F

    Sunny

Detailed Forecast

Today
Sunny, with a high near 75. Northwest wind 5 to 15 mph, with gusts as high as 25 mph.
Tonight
Increasing clouds, with a low around 45. West wind 5 to 8 mph becoming calm in the evening.
Thursday
Increasing clouds, with a high near 67. Calm wind becoming northwest 5 to 7 mph in the afternoon.
Thursday Night
Partly cloudy, with a low around 43. Calm wind.
Friday
A 20 percent chance of showers before 1pm. Mostly sunny, with a high near 72. Light and variable wind becoming south 5 to 10 mph in the afternoon. Winds could gust as high as 18 mph.
Friday Night
Mostly clear, with a low around 56. South wind around 6 mph, with gusts as high as 22 mph.
Saturday
Sunny, with a high near 81. Breezy, with a south wind 9 to 17 mph, with gusts as high as 28 mph.
Saturday Night
Mostly clear, with a low around 60. South wind 7 to 13 mph, with gusts as high as 28 mph.
Sunday
Sunny, with a high near 80. South wind 5 to 9 mph, with gusts as high as 18 mph.
Sunday Night
Partly cloudy, with a low around 56. South wind 3 to 5 mph.
Columbus Day
A 30 percent chance of showers. Partly sunny, with a high near 72. Light west wind becoming southwest 5 to 9 mph in the morning. Winds could gust as high as 18 mph.
Monday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 48. East wind around 6 mph becoming light and variable. Winds could gust as high as 18 mph.
Tuesday
A 30 percent chance of showers. Partly sunny, with a high near 63. North wind 5 to 9 mph, with gusts as high as 18 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Ontario WI
 43.73°N 90.58°W
Last Update:
9:06 am CDT Oct 7, 2026
Forecast Valid:
10am CDT Oct 7, 2026-6pm CDT Oct 13, 2026
 
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Additional Resources

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