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Old Greenwich, CT Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Old Greenwich, a community in Fairfield County, Connecticut.

Today
84°F
Mostly Sunny
Mostly sunny, with a high near 84. East wind around 5 mph.

7-day forecast for Old Greenwich

WhenTempForecastWindPrecip
Today 84°F Mostly Sunny 5 mph E 0%
Tonight 67°F Mostly Cloudy 5 mph SE 3%
Wednesday 84°F Partly Sunny then Slight Chance Showers And Thunderstorms 2 to 6 mph E 23%
Wednesday Night 72°F Chance Rain Showers 6 mph S 26%
Thursday 89°F Chance Showers And Thunderstorms 3 to 9 mph SW 39%
Thursday Night 74°F Chance Showers And Thunderstorms then Partly Cloudy 5 to 8 mph SW 38%
Friday 90°F Mostly Sunny then Chance Showers And Thunderstorms 7 mph SW 39%
Friday Night 73°F Chance Showers And Thunderstorms 7 mph SW 38%
Saturday 85°F Partly Sunny then Chance Showers And Thunderstorms 5 to 9 mph SW 30%
Saturday Night 72°F Chance Showers And Thunderstorms 8 mph SW 30%
Sunday 85°F Mostly Sunny then Slight Chance Showers And Thunderstorms 7 mph W 15%
Sunday Night 74°F Slight Chance Showers And Thunderstorms then Mostly Clear 7 mph SW 15%
Monday 87°F Sunny 5 to 12 mph W 13%
Monday Night 72°F Slight Chance Rain Showers 7 to 12 mph W 18%

Forecast source: National Weather Service (api.weather.gov) for Old Greenwich (41.020, -73.568). Updated through the day.

Growing snapshot for Old Greenwich

Last spring frost
Apr 17
First fall frost
Oct 23
Growing season
188 days
Hardiness zone
7b

More local growing data for Old Greenwich: nearby ZIP 06870 weather · frost dates · planting calendar · Connecticut frost dates

Nearby towns & communities

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Climate data from the nearest NOAA station, Stamford 5 N, Ct (7 mi from Old Greenwich). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.