PENNSYLVANIA — While October is typically known for crisp fall air and colorful foliage across Pennsylvania, history shows that measurable snowfall during the month is possible — though relatively rare.
According to past weather records from the National Weather Service, several parts of Pennsylvania have seen measurable snow in October. The earliest notable event occurred in 1972 when parts of northern and western Pennsylvania recorded snowfall before Halloween.
In higher elevations such as the Allegheny Plateau and Pocono Mountains, snow in October has been more frequent due to cooler temperatures and elevation.
For example, on October 15, 2009, portions of northwestern Pennsylvania, including areas near Erie and Bradford, recorded up to several inches of snow.
In 2011, a strong early-season storm brought measurable snow to parts of southeastern Pennsylvania, including areas around Philadelphia and the Lehigh Valley — an unusual event for that part of the state.
Mountainous areas in central and northern Pennsylvania are generally the most likely to experience measurable snow in October. In some years, Mount Davis, the state’s highest point at 3,213 feet, has seen light accumulations during mid to late October as cold air from Canada occasionally sweeps southward.
Statewide climate data show that measurable snowfall in October typically occurs only once every several years, and most often in higher elevations. Lower-lying areas, such as Pittsburgh, Harrisburg, and Philadelphia, rarely experience measurable October snow, though flurries have occasionally been observed.
While October snowfall in Pennsylvania is not an annual occurrence, the state’s varied terrain and proximity to the Great Lakes make early snow events possible. Past records confirm that when the right combination of cold air and moisture arrives early, Pennsylvania can see measurable snow well before winter officially begins.
