Allentown, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Allentown, a city in Lehigh County, Pennsylvania.
Today
85°F
Mostly Sunny
Mostly sunny, with a high near 85. Wind around 0 mph.
7-day forecast for Allentown
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 85°F | Mostly Sunny | 0 mph | 0% |
| Tonight | 64°F | Mostly Cloudy | 0 mph | 2% |
| Wednesday | 84°F | Slight Chance Rain Showers then Chance Showers And Thunderstorms | 0 to 5 mph E | 57% |
| Wednesday Night | 70°F | Showers And Thunderstorms Likely | 0 to 5 mph E | 61% |
| Thursday | 89°F | Showers And Thunderstorms Likely | 0 to 5 mph SW | 71% |
| Thursday Night | 71°F | Showers And Thunderstorms Likely | 0 to 5 mph SW | 71% |
| Friday | 89°F | Mostly Sunny then Showers And Thunderstorms Likely | 0 to 5 mph W | 56% |
| Friday Night | 70°F | Showers And Thunderstorms Likely then Chance Showers And Thunderstorms | 0 to 5 mph W | 56% |
| Saturday | 87°F | Partly Sunny then Chance Showers And Thunderstorms | 0 to 5 mph W | 42% |
| Saturday Night | 69°F | Chance Showers And Thunderstorms | 0 to 5 mph W | 42% |
| Sunday | 88°F | Mostly Sunny | 0 to 5 mph W | 12% |
| Sunday Night | 70°F | Mostly Clear | 0 to 5 mph SW | 12% |
| Monday | 90°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 0 to 10 mph W | 16% |
| Monday Night | 69°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph W | 16% |
Forecast source: National Weather Service (api.weather.gov) for Allentown (40.594, -75.478). Updated through the day.
Growing snapshot for Allentown
Last spring frost
Apr 20
First fall frost
Oct 24
Growing season
184 days
More local growing data for Allentown: nearby ZIP 18101 weather · frost dates · planting calendar · Pennsylvania frost dates
Nearby towns & communities
Alburtis
Ancient Oaks
Bethlehem
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
Climate data from the nearest NOAA station, Allentown Intl Ap, Pa (3.5 mi from Allentown). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.