Cos Cob, CT Weather & Growing Conditions
Tonight
54°F
Partly Cloudy
Partly cloudy, with a low around 54. North wind 6 to 10 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 54°F | Partly Cloudy | 6 to 10 mph N | 0% |
| Saturday | 68°F | Mostly Sunny | 7 to 10 mph E | 0% |
| Saturday Night | 58°F | Mostly Cloudy then Slight Chance Rain Showers | 6 mph SE | 16% |
| Sunday | 68°F | Showers And Thunderstorms | 5 to 12 mph SE | 88% |
| Sunday Night | 58°F | Showers And Thunderstorms | 2 to 10 mph SW | 88% |
| Monday | 67°F | Chance Rain Showers | 12 mph NE | 44% |
| Monday Night | 53°F | Chance Rain Showers | 9 to 13 mph NE | 27% |
| Tuesday | 63°F | Chance Rain Showers | 14 mph NE | 26% |
| Tuesday Night | 51°F | Chance Rain Showers then Mostly Cloudy | 15 mph NE | 26% |
| Wednesday | 63°F | Mostly Cloudy then Slight Chance Rain Showers | 16 mph NE | 15% |
| Wednesday Night | 51°F | Chance Rain Showers | 16 mph NE | 31% |
| Thursday | 63°F | Chance Rain Showers | 16 mph NE | 31% |
| Thursday Night | 51°F | Chance Rain Showers | 12 to 15 mph NE | 36% |
| Friday | 67°F | Chance Rain Showers | 14 mph N | 36% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Cos Cob, CT
Last spring frost
Apr 17
First fall frost
Oct 23
Growing season
188 days
Hardiness zone
7a
Explore more for Cos Cob, CT: full frost dates · planting calendar · Connecticut frost dates
Climate data from the nearest NOAA station, Stamford 5 N, Ct (5.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.