Norristown, Pennsylvania, gets 48 inches of rain per year. The US average is 39. Snowfall is 24 inches. The average US city gets 26 inches of snow per year. The number of days with any measurable precipitation is 116.
On average, there are 209 sunny days per year in Norristown, Pennsylvania. The July high is around 88 degrees. The January low is 22. Sperling's comfort index for Norristown is a 46 out of 100, where a higher score indicates a more comfortable year-around climate. The US average for the comfort index is 54. Our index is based on the total number of days annually within the comfort range of 70-80 degrees, and we also applied a penalty for days of excessive humidity.