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Castalia, OH Weather & Growing Conditions

Overnight
62°F
Mostly Cloudy
Mostly cloudy, with a low around 62. South wind 9 to 13 mph, with gusts as high as 25 mph.

7-day forecast

WhenTempForecastWindPrecip
Overnight 62°F Mostly Cloudy 9 to 13 mph S 9%
Wednesday 68°F Light Rain 14 to 20 mph S 92%
Wednesday Night 51°F Light Rain Likely then Cloudy 7 to 20 mph SW 57%
Thursday 62°F Partly Sunny 8 to 16 mph SW 1%
Thursday Night 46°F Mostly Cloudy then Slight Chance Rain Showers 5 to 9 mph SW 23%
Friday 55°F Rain Showers Likely 5 to 9 mph W 62%
Friday Night 39°F Rain Showers Likely 10 mph NW 60%
Saturday 52°F Chance Rain Showers 8 to 12 mph NW 33%
Saturday Night 34°F Mostly Cloudy 7 mph W 7%
Sunday 54°F Mostly Sunny 6 to 13 mph W 3%
Sunday Night 35°F Mostly Clear 6 to 9 mph W 3%
Monday 56°F Mostly Sunny 6 to 10 mph W 4%
Monday Night 39°F Partly Cloudy 8 mph SW 3%
Tuesday 60°F Mostly Sunny 8 to 12 mph W 1%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Castalia, OH

Last spring frost
Apr 10
First fall frost
Nov 5
Growing season
209 days
Hardiness zone
6b

Explore more for Castalia, OH: full frost dates · planting calendar · Ohio frost dates

Climate data from the nearest NOAA station, Sandusky, Oh (6.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.