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Hazardous Weather Conditions

Current conditions at

Selinsgrove Penn Valley Airport (KSEG)

Lat: 40.82°NLon: 76.87°WElev: 443ft.

Overcast

63°F

17°C

Humidity 97%
Wind Speed Calm
Barometer 30.05 in (1017.4 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Last update 22 Aug 9:53 am EDT
Extended Forecast for

Northumberland PA

  • Today

    Today: A chance of showers and thunderstorms, mainly between 2pm and 4pm. Partly sunny, with a high near 79. Calm wind becoming south around 6 mph in the afternoon. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 79 °F

    Partly Sunny
    then Chance
    Showers

  • Tonight

    Tonight: Showers and thunderstorms likely, then showers and possibly a thunderstorm after 2am. Patchy fog after 3am. Low around 63. Light southeast wind. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 63 °F

    Showers and
    Patchy Fog

  • Sunday

    Sunday: A chance of showers before 2pm, then a slight chance of showers and thunderstorms between 2pm and 3pm. Patchy fog before 7am. Otherwise, mostly sunny, with a high near 78. West wind 3 to 8 mph. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 78 °F

    Chance
    Showers and
    Patchy Fog
    then Slight
    Chance
    T-storms

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 57. Light southwest wind.

    Low: 57 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 74. Calm wind becoming west 5 to 8 mph in the morning. Winds could gust as high as 20 mph.

    High: 74 °F

    Mostly Sunny

  • Monday Night

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

    Low: 56 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 77.

    High: 77 °F

    Mostly Sunny

  • Tuesday Night

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

    Low: 56 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 81.

    High: 81 °F

    Mostly Sunny

Detailed Forecast

Today
A chance of showers and thunderstorms, mainly between 2pm and 4pm. Partly sunny, with a high near 79. Calm wind becoming south around 6 mph in the afternoon. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tonight
Showers and thunderstorms likely, then showers and possibly a thunderstorm after 2am. Patchy fog after 3am. Low around 63. Light southeast wind. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Sunday
A chance of showers before 2pm, then a slight chance of showers and thunderstorms between 2pm and 3pm. Patchy fog before 7am. Otherwise, mostly sunny, with a high near 78. West wind 3 to 8 mph. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday Night
Mostly clear, with a low around 57. Light southwest wind.
Monday
Mostly sunny, with a high near 74. Calm wind becoming west 5 to 8 mph in the morning. Winds could gust as high as 20 mph.
Monday Night
Mostly clear, with a low around 56.
Tuesday
Mostly sunny, with a high near 77.
Tuesday Night
Mostly clear, with a low around 56.
Wednesday
Mostly sunny, with a high near 81.
Wednesday Night
Partly cloudy, with a low around 63.
Thursday
Showers likely. Partly sunny, with a high near 82. Chance of precipitation is 60%.
Thursday Night
Showers likely. Mostly cloudy, with a low around 64. Chance of precipitation is 60%.
Friday
A chance of showers. Partly sunny, with a high near 83. Chance of precipitation is 30%.
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ABOUT THIS FORECAST

 
Point Forecast:
Northumberland PA
 40.89°N 76.79°W (Elev. 482 ft)
Last Update:
9:46 am EDT Aug 22, 2026
Forecast Valid:
10am EDT Aug 22, 2026-6pm EDT Aug 28, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation