Derby, CT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Derby, a city in New Haven County, Connecticut.
This Afternoon
80°F
Sunny
Sunny. High near 80, with temperatures falling to around 76 in the afternoon. Northwest wind around 8 mph.
7-day forecast for Derby
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 80°F | Sunny | 8 mph NW | 0% |
| Tonight | 52°F | Partly Cloudy | 5 to 9 mph N | 0% |
| Saturday | 69°F | Mostly Sunny | 5 to 8 mph E | 0% |
| Saturday Night | 55°F | Mostly Cloudy | 6 mph SE | 3% |
| Sunday | 67°F | Showers And Thunderstorms | 6 to 12 mph SE | 89% |
| Sunday Night | 55°F | Showers And Thunderstorms | 1 to 13 mph S | 89% |
| Monday | 66°F | Chance Rain Showers | 9 to 14 mph NE | 41% |
| Monday Night | 50°F | Slight Chance Rain Showers | 6 to 14 mph NE | 23% |
| Tuesday | 63°F | Slight Chance Rain Showers | 15 mph NE | 24% |
| Tuesday Night | 49°F | Mostly Cloudy | 13 to 16 mph NE | 14% |
| Wednesday | 63°F | Partly Sunny then Slight Chance Rain Showers | 17 mph NE | 15% |
| Wednesday Night | 49°F | Chance Rain Showers | 13 to 16 mph NE | 25% |
| Thursday | 63°F | Chance Rain Showers | 15 to 18 mph NE | 32% |
| Thursday Night | 49°F | Chance Rain Showers | 13 to 17 mph NE | 35% |
Forecast source: National Weather Service (api.weather.gov) for Derby (41.326, -73.083). Updated through the day.
Growing snapshot for Derby
Last spring frost
Apr 25
First fall frost
Oct 17
Growing season
175 days
Hardiness zone
6b
More local growing data for Derby: nearby ZIP 06418 weather · frost dates · planting calendar · Connecticut frost dates
Nearby towns & communities
Ansonia
Branford Center
Cheshire Village
East Haven
Guilford Center
Heritage Village
Madison Center
Meriden
Milford city
Naugatuck
New Haven
North Haven
Northford
Orange
Quinnipiac University
Wallingford Center
Waterbury
West Haven
Woodmont
Climate data from the nearest NOAA station, Ansonia 1 Ne, Ct (1.7 mi from Derby). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.