If you're looking for summer vibes, the best time to travel to Harrisburg, PA is in June, July and August, when the average temperature reaches 25.36 °C, while September, July and April are the 3 sunniest months of the year, with an average of 127.54 hours.
However, if you prefer colder temperatures, make sure you visit Harrisburg, PA during January, February or March to experience an average of -1.8 °C.
For those who don't care too much about temperatures, but want to avoid getting wet in the rain, it's important to avoid travelling during January, March and June, when the average precipitation in Harrisburg, PA is 8.25 mm, while the months of January, February and March are drier, with an average of 0 mm.