Northumberland, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Northumberland, a borough in Northumberland County, Pennsylvania.
Today
84°F
Sunny
Sunny, with a high near 84. Northeast wind around 1 mph.
7-day forecast for Northumberland
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Sunny | 1 mph NE | 0% |
| Tonight | 64°F | Mostly Cloudy | 0 mph | 2% |
| Wednesday | 82°F | Mostly Cloudy then Slight Chance Showers And Thunderstorms | 0 to 3 mph E | 20% |
| Wednesday Night | 70°F | Showers And Thunderstorms Likely | 0 to 3 mph SE | 55% |
| Thursday | 86°F | Patchy Fog then Showers And Thunderstorms | 0 to 5 mph S | 79% |
| Thursday Night | 71°F | Showers And Thunderstorms then Chance Showers And Thunderstorms | 2 mph SW | 79% |
| Friday | 86°F | Showers And Thunderstorms Likely | 0 to 3 mph SW | 73% |
| Friday Night | 68°F | Showers And Thunderstorms Likely then Chance Showers And Thunderstorms | 2 mph SW | 73% |
| Saturday | 85°F | Partly Sunny then Chance Showers And Thunderstorms | 0 to 5 mph W | 46% |
| Saturday Night | 67°F | Chance Showers And Thunderstorms | 2 mph W | 46% |
| Sunday | 87°F | Mostly Sunny | 0 to 3 mph W | 11% |
| Sunday Night | 69°F | Mostly Clear | 0 to 3 mph W | 11% |
| Monday | 89°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 0 to 7 mph W | 24% |
| Monday Night | 68°F | Slight Chance Showers And Thunderstorms | 1 to 6 mph W | 24% |
Forecast source: National Weather Service (api.weather.gov) for Northumberland (40.897, -76.793). Updated through the day.
Growing snapshot for Northumberland
Last spring frost
Apr 30
First fall frost
Oct 13
Growing season
166 days
Hardiness zone
6b
More local growing data for Northumberland: nearby ZIP 17857 weather · frost dates · planting calendar · Pennsylvania frost dates
Nearby towns & communities
Allenwood
Atlas
Dalmatia
Dewart
Edgewood
Fairview-Ferndale
Klingerstown
Kulpmont
Lewisburg
Linntown
Locust Gap
Marion Heights
Marshallton
McEwensville
Montandon
Mount Carmel
Ranshaw
Riverside
Shamokin
Snydertown
Strong
Sunbury
Tharptown (Uniontown)
Trevorton
Turbotville
Watsontown
Climate data from the nearest NOAA station, Sunbury, Pa (5.5 mi from Northumberland). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.