Union Weather Forecast

    • 57
    • 68

    Rain

    • 51
    • 70

    Rain Showers Likely

    • 48
    • 62

    Rain Showers Likely

    • 48
    • 64

    Chance Rain Showers

    • 48
    • 63

    Mostly Cloudy

    • 49
    • 65

    Chance Rain Showers

    • 50
    • 69

    Slight Chance Rain Showers

Today 20 Sep Hunterdon

Partly sunny. Highs in the lower 70s.

Tonight 20 Sep Hunterdon

Mostly cloudy. A chance of Showers with a slight chance of Thunderstorms this Evening, then a slight chance of Showers after midnight. Lows in the upper 50s. North Winds around 5 Mph. Chance of rain 50 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Union Temperature Statistics

September Temperature

Somerville, Somerset Airport (14.9 miles)

  • Lowest 15 September, 2026

    46.9 °F

  • Average September

    69.9 °F

  • Highest 1 September, 2026

    87.1 °F

Climate (2021–2026)

Somerville, Somerset Airport (14.9 miles)

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  • Average Low 2021–2026

    43 °F

  • Average 2021–2026

    54.3 °F

  • Average High 2021–2026

    65.6 °F
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