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Belfast, PA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Belfast, a community in Northampton County, Pennsylvania.

Today
72°F
Mostly Sunny
Mostly sunny, with a high near 72. East wind around 5 mph.

7-day forecast for Belfast

WhenTempForecastWindPrecip
Today 72°F Mostly Sunny 5 mph E 1%
Tonight 55°F Mostly Cloudy then Chance Rain Showers 5 mph SE 28%
Sunday 69°F Rain Showers 5 mph S 99%
Sunday Night 54°F Showers And Thunderstorms 5 to 10 mph W 85%
Monday 68°F Partly Sunny 5 to 10 mph NE 9%
Monday Night 48°F Mostly Cloudy then Chance Rain Showers 5 to 10 mph NE 30%
Tuesday 62°F Chance Rain Showers 10 mph NE 30%
Tuesday Night 47°F Chance Rain Showers 10 to 15 mph NE 28%
Wednesday 62°F Slight Chance Rain Showers 15 mph NE 24%
Wednesday Night 47°F Chance Rain Showers 10 to 15 mph NE 32%
Thursday 62°F Chance Rain Showers 10 to 15 mph NE 34%
Thursday Night 47°F Chance Rain Showers 10 to 15 mph NE 34%
Friday 65°F Chance Rain Showers 10 to 15 mph N 25%
Friday Night 48°F Chance Rain Showers 10 mph NE 25%

Forecast source: National Weather Service (api.weather.gov) for Belfast (40.782, -75.274). Updated through the day.

Growing snapshot for Belfast

Last spring frost
Apr 18
First fall frost
Oct 25
Growing season
188 days
Hardiness zone
7a

More local growing data for Belfast: nearby ZIP 18083 weather · frost dates · planting calendar · Pennsylvania frost dates

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Climate data from the nearest NOAA station, Phillipsburg-Easton Brg, Nj (5.3 mi from Belfast). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.