Historical weather data, all-time temperature records, and monthly climate averages for Harrisburg, PA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5th in Harrisburg sits right in the heart of spring's unpredictability — temperatures have swung from a bitter 25° in 2002 to a downright summery 83° just two years ago in 2023. The average lands at a mild 59° high and 38° low, though there's still a 4% chance of snow keeping winter honest. Overall, a one-in-three shot at rain means you might want a light jacket either way.
Harrisburg has seen the full extremes — from a scorching 107° on July 3, 1966 to a brutal -9° on January 22, 1984, a range of 116 degrees. The wettest single day on record dumped 9.13 inches during a June 1972 storm, while a February 1983 blizzard buried the city under 24 inches of snow. This is a city that doesn't do anything halfway.
Summer is Harrisburg's headline act, with late July averaging a toasty 88° high — but the calendar flips hard in January, when highs drop to a frigid 37°. Late May into early June is the wettest stretch of the year, averaging over an inch of rain in a single week. If you're planning a visit, aim for September or October when highs are comfortably in the 60s and 70s and the rain eases off.