Current conditions at

Sparta, Sparta / Fort McCoy Airport (KCMY)

Lat: 43.96°NLon: 90.74°WElev: 837ft.

Fair

78°F

26°C

Humidity 38%
Wind Speed Calm
Barometer 30.15 in (1021.2 mb)
Dewpoint 51°F (11°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 23 Jun 12:55 pm CDT
Extended Forecast for

Ontario WI

  • This Afternoon

    This Afternoon: Mostly sunny, with a high near 78. South wind 3 to 5 mph.

    High: 78 °F

    Mostly Sunny

  • Tonight

    Tonight: Showers and thunderstorms likely, then showers and possibly a thunderstorm after 2am.  Low around 59. South wind around 5 mph becoming calm.  Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 59 °F

    Chance
    T-storms then
    Showers

  • Wednesday

    Wednesday: Showers and thunderstorms likely before 4pm, then showers likely and possibly a thunderstorm between 4pm and 5pm, then a chance of showers and thunderstorms after 5pm.  Cloudy, then gradually becoming mostly sunny, with a high near 79. Southwest wind around 7 mph becoming west in the afternoon.  Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 79 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A 30 percent chance of showers before 7pm.  Partly cloudy, with a low around 54. Light and variable wind.

    Low: 54 °F

    Chance
    Showers then
    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 76. Calm wind.

    High: 76 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 54. Calm wind.

    Low: 54 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 78. Light and variable wind.

    High: 78 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 57. Calm wind.

    Low: 57 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 82. Calm wind becoming southeast 5 to 7 mph in the morning.

    High: 82 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Mostly sunny, with a high near 78. South wind 3 to 5 mph.
Tonight
Showers and thunderstorms likely, then showers and possibly a thunderstorm after 2am. Low around 59. South wind around 5 mph becoming calm. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Wednesday
Showers and thunderstorms likely before 4pm, then showers likely and possibly a thunderstorm between 4pm and 5pm, then a chance of showers and thunderstorms after 5pm. Cloudy, then gradually becoming mostly sunny, with a high near 79. Southwest wind around 7 mph becoming west in the afternoon. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
A 30 percent chance of showers before 7pm. Partly cloudy, with a low around 54. Light and variable wind.
Thursday
Mostly sunny, with a high near 76. Calm wind.
Thursday Night
Partly cloudy, with a low around 54. Calm wind.
Friday
Mostly sunny, with a high near 78. Light and variable wind.
Friday Night
Partly cloudy, with a low around 57. Calm wind.
Saturday
Mostly sunny, with a high near 82. Calm wind becoming southeast 5 to 7 mph in the morning.
Saturday Night
A 50 percent chance of showers and thunderstorms, mainly after 1am. Mostly cloudy, with a low around 64. Southeast wind around 7 mph, with gusts as high as 20 mph.
Sunday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 88. Breezy, with a south wind 8 to 18 mph, with gusts as high as 26 mph.
Sunday Night
A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 71. South wind 9 to 15 mph, with gusts as high as 26 mph.
Monday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 93. Breezy, with a south wind 7 to 17 mph, with gusts as high as 26 mph.
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ABOUT THIS FORECAST

 
Point Forecast:
Ontario WI
 43.73°N 90.58°W
12:31 pm CDT Jun 23, 2026
1pm CDT Jun 23, 2026-6pm CDT Jun 29, 2026
 
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