Steffan Reservoir Weather Forecast

    • 58
    • 68

    Chance Rain Showers

    • 54
    • 64

    Rain Showers

    • 49
    • 61

    Rain Showers Likely

    • 49
    • 64

    Mostly Cloudy

    • 54
    • 68

    Chance Rain Showers

    • 56
    • 69

    Slight Chance Rain Showers

Today 19 Sep Knox

Cloudy. A slight chance of Showers in the morning. Not as warm and humid. Near steady temperature in the mid 60s. North Winds 5 to 10 Mph. Chance of rain 20 percent.

Tonight 19 Sep Knox

Cloudy. A slight chance of Showers after midnight. Lows in the upper 50s. North Winds around 10 Mph. Chance of rain 20 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Steffan Reservoir Temperature Statistics

September Temperature

Yankton, Chan Gurney Municipal Airport (11.2 miles)

  • Lowest 13 September, 2026

    48.9 °F

  • Average September

    71.9 °F

  • Highest 4 September, 2026

    95 °F

Climate (2021–2026)

Yankton, Chan Gurney Municipal Airport (11.2 miles)

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  • Average Low 2021–2026

    39.4 °F

  • Average 2021–2026

    50.5 °F

  • Average High 2021–2026

    61.8 °F
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