Herndon Weather Forecast

    • 56
    • 81

    Becoming Sunny

    • 65
    • 82

    Partly Sunny

    • 66
    • 83

    Rain Showers

    • 58
    • 83

    Chance Rain Showers

    • 57
    • 80

    Mostly Sunny

    • 61
    • 83

    Partly Sunny

Today 19 Jul Northumberland

Sunny. Highs in the upper 70s. North Winds 5 to 10 Mph.

Tonight 19 Jul Northumberland

Partly cloudy. Patchy fog. Near steady temperature in the mid 60s. Northwest Winds around 5 Mph with Gusts up to 20 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Herndon Temperature Statistics

July Temperature

Selinsgrove Penn Valley Airport (7.5 miles)

  • Lowest 13 July, 2026

    64 °F

  • Average July

    77.4 °F

  • Highest 1 July, 2026

    97 °F

Climate (2021–2026)

Selinsgrove Penn Valley Airport (7.5 miles)

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  • Average Low 2021–2026

    42.3 °F

  • Average 2021–2026

    52.7 °F

  • Average High 2021–2026

    63.1 °F
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