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South Mount Vernon, OH Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for South Mount Vernon, a community in Knox County, Ohio.

Tonight
66°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely before 8pm, then a chance of showers and thunderstorms between 8pm and 11pm, then showers and thunderstorms likely. Mostly cloudy, with a low around 66. South wind around 7 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

7-day forecast for South Mount Vernon

WhenTempForecastWindPrecip
Tonight 66°F Showers And Thunderstorms Likely 7 mph S 69%
Sunday 77°F Showers And Thunderstorms 7 mph W 77%
Sunday Night 54°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 7 to 10 mph NE 57%
Monday 68°F Chance Rain Showers 13 mph NE 48%
Monday Night 52°F Slight Chance Rain Showers 13 mph NE 18%
Tuesday 68°F Chance Rain Showers 13 mph NE 26%
Tuesday Night 55°F Showers And Thunderstorms Likely 13 mph NE 70%
Wednesday 67°F Showers And Thunderstorms Likely 13 mph E 72%
Wednesday Night 52°F Showers And Thunderstorms Likely 12 mph E 72%
Thursday 68°F Chance Rain Showers then Mostly Cloudy 9 mph E 47%
Thursday Night 50°F Mostly Cloudy 7 mph NE 10%
Friday 70°F Mostly Sunny 6 to 9 mph NE 11%
Friday Night 49°F Partly Cloudy 5 to 9 mph N 11%
Saturday 72°F Mostly Sunny 8 mph NE 4%

Forecast source: National Weather Service (api.weather.gov) for South Mount Vernon (40.382, -82.502). Updated through the day.

Growing snapshot for South Mount Vernon

Last spring frost
May 1
First fall frost
Oct 10
Growing season
161 days
Hardiness zone
6a

More local growing data for South Mount Vernon: nearby ZIP 43050 weather · frost dates · planting calendar · Ohio frost dates

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Climate data from the nearest NOAA station, Fredericktown 4 S, Oh (3.6 mi from South Mount Vernon). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.