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Port Penn, DE Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Port Penn, a community in New Castle County, Delaware.

This Afternoon
77°F
Mostly Sunny
Mostly sunny, with a high near 77. East wind 5 to 10 mph.

7-day forecast for Port Penn

WhenTempForecastWindPrecip
This Afternoon 77°F Mostly Sunny 5 to 10 mph E 2%
Tonight 65°F Mostly Cloudy 5 to 10 mph SE 7%
Sunday 80°F Chance Rain Showers 5 to 10 mph S 30%
Sunday Night 63°F Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 5 to 10 mph NW 71%
Monday 71°F Chance Rain Showers 10 mph NE 30%
Monday Night 58°F Chance Rain Showers 10 mph NE 36%
Tuesday 66°F Chance Rain Showers 10 to 15 mph NE 44%
Tuesday Night 56°F Chance Rain Showers 10 to 15 mph NE 42%
Wednesday 65°F Chance Rain Showers 15 mph NE 32%
Wednesday Night 56°F Chance Rain Showers 10 to 15 mph NE 34%
Thursday 64°F Chance Rain Showers 15 mph NE 34%
Thursday Night 55°F Chance Rain Showers 10 to 15 mph N 34%
Friday 67°F Chance Rain Showers 10 mph N 25%
Friday Night 54°F Slight Chance Rain Showers 5 to 10 mph N 23%

Forecast source: National Weather Service (api.weather.gov) for Port Penn (39.515, -75.581). Updated through the day.

Growing snapshot for Port Penn

Last spring frost
Apr 7
First fall frost
Nov 1
Growing season
209 days
Hardiness zone
7b

More local growing data for Port Penn: nearby ZIP 19731 weather · frost dates · planting calendar · Delaware frost dates

Nearby towns & communities

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Climate data from the nearest NOAA station, Wilmington New Castle Co Ap, De (11.3 mi from Port Penn). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.