Northumberland, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Northumberland, a borough in Northumberland County, Pennsylvania.
This Afternoon
73°F
Partly Sunny
Partly sunny, with a high near 73. Southeast wind around 2 mph.
7-day forecast for Northumberland
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 73°F | Partly Sunny | 2 mph SE | 2% |
| Tonight | 59°F | Rain Showers | 1 to 8 mph SE | 83% |
| Sunday | 72°F | Rain Showers | 3 to 9 mph S | 95% |
| Sunday Night | 53°F | Showers And Thunderstorms | 3 to 8 mph NW | 91% |
| Monday | 68°F | Mostly Cloudy | 7 mph N | 7% |
| Monday Night | 49°F | Chance Rain Showers | 5 mph NE | 41% |
| Tuesday | 62°F | Chance Rain Showers | 5 mph NE | 45% |
| Tuesday Night | 47°F | Chance Rain Showers | 6 mph E | 36% |
| Wednesday | 62°F | Chance Rain Showers | 7 mph E | 36% |
| Wednesday Night | 47°F | Chance Rain Showers | 6 mph NE | 35% |
| Thursday | 63°F | Chance Rain Showers | 6 mph NE | 35% |
| Thursday Night | 47°F | Chance Rain Showers | 5 mph NE | 34% |
| Friday | 67°F | Chance Rain Showers | 3 to 7 mph N | 25% |
| Friday Night | 48°F | Slight Chance Rain Showers | 6 mph N | 23% |
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 Sep 19, 2026.