Northumberland, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Northumberland, a borough in Northumberland County, Pennsylvania.
Overnight
47°F
Patchy Fog
Patchy fog. Partly cloudy, with a low around 47. South wind around 1 mph.
7-day forecast for Northumberland
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 47°F | Patchy Fog | 1 mph S | 0% |
| Wednesday | 73°F | Patchy Fog then Mostly Sunny | 0 to 8 mph S | 1% |
| Wednesday Night | 59°F | Mostly Cloudy then Light Rain | 5 to 8 mph S | 77% |
| Thursday | 73°F | Light Rain | 3 to 9 mph S | 91% |
| Thursday Night | 52°F | Chance Light Rain then Mostly Cloudy | 2 mph SW | 33% |
| Friday | 68°F | Slight Chance Light Rain | 1 mph NW | 16% |
| Friday Night | 45°F | Partly Cloudy | 1 mph NW | 13% |
| Saturday | 61°F | Slight Chance Light Rain | 2 to 8 mph W | 23% |
| Saturday Night | 39°F | Slight Chance Light Rain | 7 mph W | 23% |
| Sunday | 58°F | Mostly Sunny | 3 to 7 mph W | 5% |
| Sunday Night | 36°F | Partly Cloudy | 5 mph W | 6% |
| Monday | 59°F | Mostly Sunny | 5 to 9 mph W | 9% |
| Monday Night | 34°F | Partly Cloudy | 5 mph W | 8% |
| Tuesday | 63°F | Mostly Sunny | 2 to 8 mph SW | 3% |
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 Nov 4, 2026.