Bethlehem, PA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Bethlehem, a city in Lehigh County, Pennsylvania.

Today

69°F

Mostly Sunny

Mostly sunny, with a high near 69. Southwest wind 0 to 5 mph.

7-day forecast for Bethlehem

When	Temp	Forecast	Wind	Precip
Today	69°F	Mostly Sunny	0 to 5 mph SW	2%
Tonight	47°F	Areas Of Fog	0 mph	2%
Wednesday	73°F	Patchy Fog then Partly Sunny	0 to 5 mph S	2%
Wednesday Night	56°F	Mostly Cloudy	0 to 5 mph S	10%
Thursday	72°F	Light Rain Likely	5 mph S	70%
Thursday Night	59°F	Light Rain Likely	0 to 5 mph SW	71%
Friday	70°F	Light Rain Likely	0 mph	71%
Friday Night	50°F	Light Rain Likely	0 mph	68%
Saturday	66°F	Slight Chance Light Rain	0 to 5 mph NW	24%
Saturday Night	42°F	Slight Chance Light Rain then Partly Cloudy	0 to 5 mph NW	20%
Sunday	62°F	Mostly Sunny	0 to 5 mph NW	14%
Sunday Night	39°F	Partly Cloudy then Slight Chance Light Rain	0 mph	24%
Monday	58°F	Chance Light Rain	0 to 10 mph NW	34%
Monday Night	39°F	Chance Light Rain	5 mph W	34%

Forecast source: National Weather Service (api.weather.gov) for Bethlehem (40.626, -75.368). Updated through the day.

Growing snapshot for Bethlehem

Last spring frost

Apr 20

First fall frost

Oct 24

Growing season

184 days

Hardiness zone

More local growing data for Bethlehem: nearby ZIP 18018 weather · frost dates · planting calendar · Pennsylvania frost dates

Nearby towns & communities

Alburtis Allentown Ancient Oaks Breinigsville Catasauqua Cementon Cetronia Coopersburg Coplay DeSales University Dorneyville Egypt Emmaus Fountain Hill Fullerton Hokendauqua Laurys Station Macungie New Tripoli North Catasauqua Schnecksville Slatedale Slatington Stiles Trexlertown Wescosville

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Climate data from the nearest NOAA station, Allentown Intl Ap, Pa (3.2 mi from Bethlehem). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.