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Cornwall, CT Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Cornwall, a community in Litchfield County, Connecticut.

Today
68°F
Mostly Sunny
Mostly sunny, with a high near 68. Southeast wind around 3 mph.

7-day forecast for Cornwall

WhenTempForecastWindPrecip
Today 68°F Mostly Sunny 3 mph SE 0%
Tonight 48°F Mostly Cloudy 2 mph SE 6%
Sunday 60°F Rain 2 to 6 mph SE 98%
Sunday Night 48°F Rain then Rain Showers Likely 1 to 7 mph NE 90%
Monday 66°F Partly Sunny 7 mph N 4%
Monday Night 44°F Mostly Cloudy 5 mph NE 3%
Tuesday 61°F Mostly Cloudy 6 mph NE 5%
Tuesday Night 43°F Mostly Cloudy 3 to 9 mph NE 5%
Wednesday 63°F Partly Sunny 10 mph NE 4%
Wednesday Night 43°F Mostly Cloudy then Slight Chance Rain Showers 7 to 12 mph NE 24%
Thursday 61°F Chance Rain Showers 8 to 13 mph NE 31%
Thursday Night 44°F Chance Rain Showers 7 to 12 mph NE 37%
Friday 63°F Chance Rain Showers 8 to 12 mph N 35%
Friday Night 45°F Chance Rain Showers 7 to 13 mph N 33%

Forecast source: National Weather Service (api.weather.gov) for Cornwall (41.844, -73.333). Updated through the day.

Growing snapshot for Cornwall

Last spring frost
May 11
First fall frost
Oct 4
Growing season
146 days
Hardiness zone
6a

More local growing data for Cornwall: nearby ZIP 06753 weather · frost dates · planting calendar · Connecticut frost dates

Nearby towns & communities

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Climate data from the nearest NOAA station, Falls Village, Ct (8.7 mi from Cornwall). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.