FPUS41 KBGM 202132 City Forecast for Penn Yan, NY Issued Thursday afternoon - Nov 20, 2014 .Thursday night... Low 18, 50% chance of precipitation. .Friday... Snow showers, high 28, 60% chance of precipitation. .Friday night... Low 17, 10% chance of precipitation. .Saturday... Partly cloudy, high 40. .Saturday night... Low 37.