National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Selinsgrove Penn Valley Airport (KSEG)

Lat: 40.82°NLon: 76.87°WElev: 443ft.

A Few Clouds

61°F

16°C

Humidity 81%
Wind Speed Calm
Barometer 29.88 in (1011.6 mb)
Dewpoint 55°F (13°C)
Visibility 10.00 mi
Last update 20 Jun 9:53 pm EDT
Extended Forecast for

Northumberland PA

  • Tonight

    Tonight: Partly cloudy, with a low around 57. Calm wind.

    Low: 57 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 81. Calm wind becoming west around 6 mph in the morning.

    High: 81 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 59. Calm wind.

    Low: 59 °F

    Mostly Cloudy

  • Monday

    Monday: Showers, with thunderstorms also possible after 2pm. Some of the storms could produce heavy rainfall. High near 74. Calm wind becoming southeast around 6 mph in the afternoon. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.

    High: 74 °F

    Heavy Rain

  • Monday Night

    Monday Night: Showers and possibly a thunderstorm before 2am, then a chance of showers. Low around 61. Calm wind becoming northwest around 5 mph after midnight. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 61 °F

    Showers

  • Tuesday

    Tuesday: A chance of showers before 8am. Partly sunny, with a high near 80. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

    High: 80 °F

    Chance
    Showers then
    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 56.

    Low: 56 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 82.

    High: 82 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 60.

    Low: 60 °F

    Partly Cloudy

Detailed Forecast

Tonight
Partly cloudy, with a low around 57. Calm wind.
Sunday
Mostly sunny, with a high near 81. Calm wind becoming west around 6 mph in the morning.
Sunday Night
Mostly cloudy, with a low around 59. Calm wind.
Monday
Showers, with thunderstorms also possible after 2pm. Some of the storms could produce heavy rainfall. High near 74. Calm wind becoming southeast around 6 mph in the afternoon. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
Monday Night
Showers and possibly a thunderstorm before 2am, then a chance of showers. Low around 61. Calm wind becoming northwest around 5 mph after midnight. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Tuesday
A chance of showers before 8am. Partly sunny, with a high near 80. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.
Tuesday Night
Mostly clear, with a low around 56.
Wednesday
Sunny, with a high near 82.
Wednesday Night
Partly cloudy, with a low around 60.
Thursday
Showers likely and possibly a thunderstorm, mainly after 2pm. Partly sunny, with a high near 82. Chance of precipitation is 60%.
Thursday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 61. Chance of precipitation is 60%.
Friday
A chance of showers and thunderstorms. Partly sunny, with a high near 82. Chance of precipitation is 30%.
Friday Night
A chance of thunderstorms. Partly cloudy, with a low around 60. Chance of precipitation is 30%.
Saturday
Mostly sunny, with a high near 83.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Northumberland PA
 40.89°N 76.79°W (Elev. 482 ft)
Last Update:
8:11 pm EDT Jun 20, 2026
Forecast Valid:
10pm EDT Jun 20, 2026-6pm EDT Jun 27, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation