Hottest and Coldest Temperatures Ever in Allentown on December 20

On December 20th, Allentown experienced a range of temperatures. The hottest temperature ever recorded on this date was a comfortable 63.0°F in 1957, while the coldest temperature dipped to a bone-chilling -2.0°F in 1951. The average temperature for December 20th stands at 31.22°F, with an average high of 38.34°F and an average low of 24.10°F. In 1957, Allentown residents witnessed an interesting event as the world's first commercial nuclear power reactor generated electricity for the first time, marking a significant milestone in energy production.