Jamestown Weather Forecast

    • 49
    • 64

    Rain Showers Likely

    • 48
    • 57

    Rain Showers Likely

    • 44
    • 54

    Chance Rain Showers

    • 42
    • 55

    Mostly Sunny

    • 47
    • 66

    Mostly Sunny

    • 44
    • 65

    Slight Chance Rain Showers

    • 46
    • 61

    Mostly Sunny

Today 28 Sep Larimer and Boulder Counties Between 6000 and 9000 Feet

Mostly sunny. Highs 64 to 74.

Tonight 28 Sep Larimer and Boulder Counties Between 6000 and 9000 Feet

Showers likely in the Evening, then a chance of Showers after midnight. Lows 42 to 52. Chance of rain 60 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Jamestown Temperature Statistics

September Temperature

Boulder Municipal Airport (9.9 miles)

  • Lowest 22 September, 2026

    50 °F

  • Average September

    70.2 °F

  • Highest 13 September, 2026

    96.8 °F

Climate (2021–2026)

Boulder Municipal Airport (9.9 miles)

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  • Average Low 2021–2026

    41.4 °F

  • Average 2021–2026

    53.7 °F

  • Average High 2021–2026

    66.4 °F
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