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
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| 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.