Hottest and Coldest Temperatures Ever in Philadelphia on April 11

On April 11th in Philadelphia, historical weather data indicates a range of temperatures, with the hottest temperature on record being 82.9°F in 1955, and the coldest being 28.0°F in 1966. The average temperature for this date is 50.70°F, with an average high of 56.15°F and an average low of 45.26°F. In 1955, an interesting news item was that Jonas Salk's polio vaccine was declared safe and effective, providing hope in the fight against the debilitating disease.