Derby, CT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Derby, a city in New Haven County, Connecticut.
Today
84°F
Mostly Sunny
Mostly sunny, with a high near 84. Southeast wind around 5 mph.
7-day forecast for Derby
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Mostly Sunny | 5 mph SE | 0% |
| Tonight | 62°F | Mostly Cloudy | 3 mph NW | 3% |
| Wednesday | 83°F | Partly Sunny | 5 mph SW | 9% |
| Wednesday Night | 69°F | Slight Chance Rain Showers | 5 mph S | 23% |
| Thursday | 88°F | Chance Showers And Thunderstorms | 2 to 9 mph SW | 43% |
| Thursday Night | 72°F | Chance Showers And Thunderstorms then Partly Cloudy | 2 to 8 mph SW | 37% |
| Friday | 89°F | Mostly Sunny then Chance Showers And Thunderstorms | 2 to 7 mph SW | 41% |
| Friday Night | 70°F | Chance Showers And Thunderstorms | 2 to 6 mph SW | 39% |
| Saturday | 87°F | Mostly Sunny then Chance Showers And Thunderstorms | 2 to 8 mph W | 37% |
| Saturday Night | 69°F | Chance Showers And Thunderstorms | 2 to 6 mph W | 37% |
| Sunday | 88°F | Mostly Sunny | 2 to 7 mph W | 12% |
| Sunday Night | 70°F | Mostly Clear | 2 to 6 mph SW | 10% |
| Monday | 90°F | Sunny | 2 to 10 mph W | 14% |
| Monday Night | 68°F | Slight Chance Rain Showers | 3 to 8 mph W | 15% |
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 Aug 4, 2026.