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.

Rain Fog/Mist

40°F

4°C

Humidity 96%
Wind Speed E 3 mph
Barometer 29.44 in (998.1 mb)
Dewpoint 39°F (4°C)
Visibility 3.00 mi
Last update 8 Jan 6:55 pm CST
Extended Forecast for

Ontario WI

  • Tonight

    Tonight: Rain and snow before 5am, then a chance of snow. Low around 31. Blustery, with a northeast wind 9 to 16 mph becoming northwest after midnight. Winds could gust as high as 31 mph. Chance of precipitation is 100%. Little or no snow accumulation expected.

    Low: 31 °F

    Rain then
    Rain/Snow and
    Blustery

  • Friday

    Friday: A 30 percent chance of snow before 7am. Cloudy through mid morning, then gradual clearing, with a steady temperature around 35. Northwest wind 10 to 15 mph becoming light in the afternoon. Winds could gust as high as 29 mph.

    High: 35 °F

    Chance Snow
    then Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 25. Calm wind.

    Low: 25 °F

    Mostly Cloudy

  • Saturday

    Saturday: A 50 percent chance of snow. Mostly cloudy, with a high near 32. Light west wind becoming northwest 8 to 13 mph in the morning. Winds could gust as high as 23 mph. New snow accumulation of less than one inch possible.

    High: 32 °F

    Chance Snow

  • Saturday Night

    Saturday Night: A 30 percent chance of snow, mainly before midnight. Mostly cloudy, with a low around 16. Northwest wind 9 to 11 mph, with gusts as high as 23 mph.

    Low: 16 °F

    Chance Snow

  • Sunday

    Sunday: Mostly sunny, with a high near 29. Northwest wind 5 to 9 mph, with gusts as high as 20 mph.

    High: 29 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 18. Southwest wind around 6 mph.

    Low: 18 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 40. West wind 6 to 8 mph.

    High: 40 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 29. West wind 3 to 6 mph.

    Low: 29 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Rain and snow before 5am, then a chance of snow. Low around 31. Blustery, with a northeast wind 9 to 16 mph becoming northwest after midnight. Winds could gust as high as 31 mph. Chance of precipitation is 100%. Little or no snow accumulation expected.
Friday
A 30 percent chance of snow before 7am. Cloudy through mid morning, then gradual clearing, with a steady temperature around 35. Northwest wind 10 to 15 mph becoming light in the afternoon. Winds could gust as high as 29 mph.
Friday Night
Mostly cloudy, with a low around 25. Calm wind.
Saturday
A 50 percent chance of snow. Mostly cloudy, with a high near 32. Light west wind becoming northwest 8 to 13 mph in the morning. Winds could gust as high as 23 mph. New snow accumulation of less than one inch possible.
Saturday Night
A 30 percent chance of snow, mainly before midnight. Mostly cloudy, with a low around 16. Northwest wind 9 to 11 mph, with gusts as high as 23 mph.
Sunday
Mostly sunny, with a high near 29. Northwest wind 5 to 9 mph, with gusts as high as 20 mph.
Sunday Night
Partly cloudy, with a low around 18. Southwest wind around 6 mph.
Monday
Mostly sunny, with a high near 40. West wind 6 to 8 mph.
Monday Night
Mostly cloudy, with a low around 29. West wind 3 to 6 mph.
Tuesday
A slight chance of rain before noon, then a chance of rain and snow. Mostly cloudy, with a high near 40. Light and variable wind becoming west 5 to 7 mph in the morning. Chance of precipitation is 40%.
Tuesday Night
A chance of rain and snow. Mostly cloudy, with a low around 23. North wind around 6 mph. Chance of precipitation is 30%.
Wednesday
A 20 percent chance of snow. Mostly cloudy, with a high near 30. North wind 6 to 9 mph.
Wednesday Night
Mostly cloudy, with a low around 14. North wind around 6 mph becoming calm in the evening.
Thursday
A 20 percent chance of snow. Partly sunny, with a high near 28. Calm wind becoming southwest 5 to 7 mph in the morning.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Ontario WI
 43.73°N 90.58°W
Last Update:
5:26 pm CST Jan 8, 2026
Forecast Valid:
7pm CST Jan 8, 2026-6pm CST Jan 15, 2026
 
Forecast Discussion
 
Get as KML Get as XML

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation