St Johns Weather Forecast

    • 46
    • 65

    Rain Showers Likely

    • 49
    • 67

    Partly Sunny

    • 61
    • 69

    Rain Showers

    • 61
    • 77

    Chance Thunderstorms

    • 62
    • 80

    Rain Showers Likely

    • 62
    • 79

    Chance Rain Showers

Today 20 May Mercer

Mostly cloudy. Showers likely with a slight chance of Thunderstorms this Morning, then a chance of Showers this afternoon. Much cooler with Highs in the mid 60s. North Winds around 10 Mph, becoming northeast with Gusts up to 20 Mph late. Chance of rain 60 percent.

Tonight 20 May Mercer

Mostly cloudy in the Evening, then becoming partly cloudy. Lows in the mid 40s. Northeast Winds 5 to 10 Mph with Gusts up to 20 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

St Johns Temperature Statistics

May Temperature

Versailles Darke County Airport (14.3 miles)

  • Lowest 2 May, 2026

    33.8 °F

  • Average May

    55.6 °F

  • Highest 17 May, 2026

    84.2 °F

Climate (2021–Present)

Versailles Darke County Airport (14.3 miles)

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  • Average Low 2021–2026

    43.3 °F

  • Average 2021–2026

    52.5 °F

  • Average High 2021–2026

    61.8 °F
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