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

42°F

6°C

Humidity 85%
Wind Speed Calm
Barometer 29.90 in (1013.2 mb)
Dewpoint 38°F (3°C)
Visibility 10.00 mi
Last update 11 Nov 4:55 am CST
Extended Forecast for

Ontario WI

  • Overnight

    Overnight: A 20 percent chance of showers. Cloudy, with a steady temperature around 41. Calm wind.

    Low: 41 °F

    Slight Chance
    Showers

  • Veterans Day

    Veterans Day: A 20 percent chance of showers between 3pm and 5pm. Mostly cloudy, with a high near 55. Calm wind becoming northwest 5 to 8 mph in the afternoon. Winds could gust as high as 21 mph.

    High: 55 °F

    Slight Chance
    Showers

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 31. North wind around 8 mph, with gusts as high as 23 mph.

    Low: 31 °F

    Mostly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 42. North wind 8 to 14 mph, with gusts as high as 24 mph.

    High: 42 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 22. North wind around 6 mph becoming calm in the evening.

    Low: 22 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 40. Calm wind becoming north 5 to 8 mph.

    High: 40 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 20. Calm wind.

    Low: 20 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 45. Calm wind.

    High: 45 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 22. Calm wind.

    Low: 22 °F

    Mostly Clear

Detailed Forecast

Overnight
A 20 percent chance of showers. Cloudy, with a steady temperature around 41. Calm wind.
Veterans Day
A 20 percent chance of showers between 3pm and 5pm. Mostly cloudy, with a high near 55. Calm wind becoming northwest 5 to 8 mph in the afternoon. Winds could gust as high as 21 mph.
Wednesday Night
Mostly cloudy, with a low around 31. North wind around 8 mph, with gusts as high as 23 mph.
Thursday
Partly sunny, with a high near 42. North wind 8 to 14 mph, with gusts as high as 24 mph.
Thursday Night
Partly cloudy, with a low around 22. North wind around 6 mph becoming calm in the evening.
Friday
Mostly sunny, with a high near 40. Calm wind becoming north 5 to 8 mph.
Friday Night
Mostly clear, with a low around 20. Calm wind.
Saturday
Sunny, with a high near 45. Calm wind.
Saturday Night
Mostly clear, with a low around 22. Calm wind.
Sunday
Sunny, with a high near 47. Calm wind.
Sunday Night
Partly cloudy, with a low around 25. Calm wind.
Monday
Mostly sunny, with a high near 50. Light and variable wind.
Monday Night
Mostly clear, with a low around 27. Calm wind.
Tuesday
Sunny, with a high near 53. Calm wind becoming south 5 to 8 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Ontario WI
 43.73°N 90.58°W
Last Update:
5:16 am CST Nov 11, 2026
Forecast Valid:
5am CST Nov 11, 2026-6pm CST Nov 17, 2026
 
Forecast Discussion
 
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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