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Duncannon, PA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Duncannon, a borough in Perry County, Pennsylvania.

This Afternoon
75°F
Slight Chance Rain Showers
A slight chance of rain showers. Partly sunny, with a high near 75. Southeast wind around 3 mph. Chance of precipitation is 20%.

7-day forecast for Duncannon

WhenTempForecastWindPrecip
This Afternoon 75°F Slight Chance Rain Showers 3 mph SE 15%
Tonight 62°F Rain Showers 3 to 9 mph SE 79%
Sunday 78°F Rain Showers 3 to 9 mph S 92%
Sunday Night 55°F Showers And Thunderstorms Likely then Mostly Cloudy 3 to 9 mph NW 74%
Monday 70°F Partly Sunny then Chance Rain Showers 8 mph N 29%
Monday Night 52°F Rain Showers Likely 3 to 7 mph NE 59%
Tuesday 63°F Rain Showers Likely 7 mph NE 59%
Tuesday Night 50°F Chance Rain Showers 8 mph E 46%
Wednesday 61°F Chance Rain Showers 8 mph E 38%
Wednesday Night 49°F Chance Rain Showers 8 mph NE 30%
Thursday 62°F Slight Chance Rain Showers 8 mph NE 22%
Thursday Night 49°F Slight Chance Rain Showers 2 to 6 mph NE 20%
Friday 67°F Slight Chance Rain Showers 5 to 8 mph N 24%
Friday Night 50°F Slight Chance Rain Showers 5 to 9 mph N 24%

Forecast source: National Weather Service (api.weather.gov) for Duncannon (40.395, -77.028). Updated through the day.

Growing snapshot for Duncannon

Last spring frost
Apr 15
First fall frost
Oct 23
Growing season
189 days
Hardiness zone
7a

More local growing data for Duncannon: nearby ZIP 17020 weather · frost dates · planting calendar · Pennsylvania frost dates

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Climate data from the nearest NOAA station, Harrisburg 1 Ne, Pa (12.8 mi from Duncannon). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.