FPUS41 KILN 200738 City Forecast for Dayton, OH Issued Thursday morning - Oct 20, 2005 .Thursday... Showers, high 58, 60% chance of precipitation. .Thursday night... Low 46, 80% chance of precipitation. .Friday... Showers, high 54, 80% chance of precipitation. .Friday night... Low 43. .Saturday... High 55.