Grinnell Lake Weather Forecast

    • 32
    • 50

    Chance Rain Showers

    • 30
    • 51

    Slight Chance Thunderstorms

    • 23
    • 46

    Breezy

    • 19
    • 35

    Snow Showers Likely

    • 22
    • 36

    Chance Snow Showers

    • 28
    • 44

    Mostly Sunny

Today 24 May Upper San Joaquin River

Sunny in the Morning, then partly sunny with chance of rain Showers in the afternoon. Highs 50 to 68. Southeast Winds up to 5 Mph shifting to the southwest in the afternoon. Chance of Showers 50 percent.

Tonight 24 May Upper San Joaquin River

Partly cloudy. Lows 35 to 47. Southeast Winds up to 5 Mph with Gusts to around 20 Mph shifting to the east after midnight.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Grinnell Lake Temperature Statistics

May Temperature

Mammoth Yosemite Airport (10.6 miles)

  • Lowest 18 May, 2026

    19.4 °F

  • Average May

    53 °F

  • Highest 10 May, 2026

    78.8 °F

Climate (2021–Present)

Mammoth Yosemite Airport (10.6 miles)

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  • Average Low 2021–2026

    29.6 °F

  • Average 2021–2026

    45.9 °F

  • Average High 2021–2026

    60.7 °F
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