Cos Cob, CT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Cos Cob, a community in Fairfield County, Connecticut.
This Afternoon
70°F
Mostly Sunny
Mostly sunny. High near 70, with temperatures falling to around 65 in the afternoon. Southwest wind around 8 mph.
7-day forecast for Cos Cob
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 70°F | Mostly Sunny | 8 mph SW | 0% |
| Tonight | 51°F | Patchy Fog | 5 mph SW | 3% |
| Wednesday | 72°F | Patchy Fog then Sunny | 3 to 10 mph SW | 3% |
| Wednesday Night | 57°F | Partly Cloudy | 3 to 7 mph SW | 2% |
| Thursday | 72°F | Chance Rain Showers | 3 to 9 mph S | 42% |
| Thursday Night | 60°F | Rain Showers | 3 to 7 mph S | 82% |
| Friday | 69°F | Showers And Thunderstorms | 5 mph S | 85% |
| Friday Night | 54°F | Showers And Thunderstorms then Light Rain Likely | 5 mph W | 85% |
| Saturday | 66°F | Chance Light Rain | 5 to 8 mph NW | 52% |
| Saturday Night | 42°F | Slight Chance Light Rain | 8 mph NW | 19% |
| Sunday | 61°F | Slight Chance Light Rain then Mostly Sunny | 8 mph W | 18% |
| Sunday Night | 39°F | Partly Cloudy | 7 mph W | 14% |
| Monday | 60°F | Slight Chance Light Rain | 8 to 14 mph NW | 24% |
| Monday Night | 38°F | Chance Light Rain | 7 to 10 mph W | 27% |
Forecast source: National Weather Service (api.weather.gov) for Cos Cob (41.049, -73.592). Updated through the day.
Growing snapshot for Cos Cob
Last spring frost
Apr 17
First fall frost
Oct 23
Growing season
188 days
Hardiness zone
7a
More local growing data for Cos Cob: nearby ZIP 06807 weather · frost dates · planting calendar · Connecticut frost dates
Nearby towns & communities
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Brookfield Center
Candlewood Isle
Candlewood Knolls
Candlewood Lake Club
Candlewood Orchards
Candlewood Shores
Cannondale
Chimney Point
Coleytown
Compo
Danbury
Daniels Farm
Darien Downtown
Dodgingtown
East Village
Fairfield University
Georgetown
Greens Farms
Greenwich
Hawleyville
Indian Field
Inglenook
Kellogg Point
Climate data from the nearest NOAA station, Stamford 5 N, Ct (5.2 mi from Cos Cob). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.