Historical weather data, all-time temperature records, and monthly climate averages for Lancaster, PA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5th in Lancaster runs mild but unpredictable — the average high is 58° with a low near 38°, but the date has seen everything from a balmy 85° as recently as 2023 to a bitter 25° back in 1949. Rain is possible (about a 1-in-3 shot), though snow is essentially off the table at this point in spring.
Lancaster's weather has some real teeth at the extremes — the thermometer has hit 103° in the summer of 2011 and plunged to -16° in January 1984, a swing of nearly 120 degrees. The wettest single day on record dumped 6.11 inches in September 1999, and a January 2016 snowstorm buried the area under 19 inches in a single day.
Lancaster's peak summer heat arrives mid-to-late July, when average highs reach 88° — and that's also the wettest stretch of the year, averaging over an inch of rain in a single week. Winter bottoms out in mid-January with average highs of just 37°, so if you're planning a visit, May through June offers warm temps in the 70s before the summer humidity kicks in.