Grand Lake St. Marys SPB Weather Forecast

    • 63
    • 84

    Chance Thunderstorms

    • 72
    • 84

    Chance Rain Showers

    • 72
    • 86

    Rain Showers Likely

    • 69
    • 83

    Rain Showers Likely

    • 66
    • 81

    Rain Showers Likely

    • 63
    • 79

    Chance Thunderstorms

Today 8 Aug Mercer

Partly cloudy. Patchy fog this morning. A chance of Showers and Thunderstorms this afternoon. Highs in the mid 80s. Southwest Winds 5 to 10 Mph. Chance of rain 40 percent.

Tonight 8 Aug Mercer

Mostly clear. A slight chance of Showers and Thunderstorms in the evening. Lows around 60. Northwest Winds 5 to 10 Mph. Chance of rain 20 percent.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Grand Lake St. Marys SPB Temperature Statistics

August Temperature

Versailles Darke County Airport (23 miles)

  • Lowest 4 August, 2026

    53.6 °F

  • Average August

    70.5 °F

  • Highest 6 August, 2026

    84.2 °F

Climate (2021–2026)

Versailles Darke County Airport (23 miles)

Take a look at our website widgetsAvailable free! Find Out More

  • Average Low 2021–2026

    43.3 °F

  • Average 2021–2026

    52.5 °F

  • Average High 2021–2026

    61.8 °F
Get WillyWeather+ to remove ads