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

Hazardous Weather Conditions

Current conditions at

Sparta, Sparta / Fort McCoy Airport (KCMY)

Lat: 43.96°NLon: 90.74°WElev: 837ft.

Fair

79°F

26°C

Humidity 44%
Wind Speed S 3 mph
Barometer 30.13 in (1020.6 mb)
Dewpoint 56°F (13°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 3 Aug 3:55 pm CDT
Extended Forecast for

Ontario WI

  • Tonight

    Tonight: Areas of smoke. Partly cloudy, with a low around 56. Light southeast wind.

    Low: 56 °F

    Areas Smoke

  • Monday

    Monday: Areas of smoke. Mostly sunny, with a high near 81. Calm wind becoming southeast 5 to 7 mph in the morning.

    High: 81 °F

    Areas Smoke

  • Monday Night

    Monday Night: Areas of smoke before 4am. Partly cloudy, with a low around 59. Calm wind.

    Low: 59 °F

    Areas Smoke

  • Tuesday

    Tuesday: Mostly sunny, with a high near 83. Calm wind becoming southeast around 6 mph in the afternoon.

    High: 83 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 61. Calm wind.

    Low: 61 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 86. Calm wind becoming south around 6 mph in the afternoon.

    High: 86 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 66. Light south wind.

    Low: 66 °F

    Partly Cloudy
    then Slight
    Chance
    T-storms

  • Thursday

    Thursday: Mostly sunny, with a high near 88. Calm wind becoming south 5 to 7 mph in the morning.

    High: 88 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 69. South wind around 5 mph becoming calm in the evening.

    Low: 69 °F

    Partly Cloudy

Detailed Forecast

Tonight
Areas of smoke. Partly cloudy, with a low around 56. Light southeast wind.
Monday
Areas of smoke. Mostly sunny, with a high near 81. Calm wind becoming southeast 5 to 7 mph in the morning.
Monday Night
Areas of smoke before 4am. Partly cloudy, with a low around 59. Calm wind.
Tuesday
Mostly sunny, with a high near 83. Calm wind becoming southeast around 6 mph in the afternoon.
Tuesday Night
Mostly clear, with a low around 61. Calm wind.
Wednesday
Mostly sunny, with a high near 86. Calm wind becoming south around 6 mph in the afternoon.
Wednesday Night
A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 66. Light south wind.
Thursday
Mostly sunny, with a high near 88. Calm wind becoming south 5 to 7 mph in the morning.
Thursday Night
Partly cloudy, with a low around 69. South wind around 5 mph becoming calm in the evening.
Friday
Mostly sunny, with a high near 91. South wind 5 to 9 mph.
Friday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 71. South wind around 7 mph.
Saturday
Mostly sunny, with a high near 90. South wind 6 to 9 mph, with gusts as high as 18 mph.
Saturday Night
A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 69. South wind around 6 mph.
Sunday
A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 88. Southwest wind 5 to 7 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:
4:29 pm CDT Aug 3, 2025
Forecast Valid:
4pm CDT Aug 3, 2025-6pm CDT Aug 10, 2025
 
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Additional Resources

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Chance of Precipitation