Erie has a humid continental climate (Köppen Dfb) that is shaped, more than anywhere else in Pennsylvania, by the water it sits on. Lake Erie keeps summers comparatively mild and stretches autumn warmth later into the year — but once cold air sweeps across the still-open lake in late fall and early winter, it sets off the snow machine the city is famous for.
Lake-effect snow is the headline. Erie averages around 100 inches of snow a year — among the highest of any U.S. city — and a single setup can bury neighborhoods in several feet while a town 30 miles inland sees flurries. The heaviest lake-effect runs from late November into January, before the lake ices over. Summers are pleasant, with highs typically in the low 80s and a reliable afternoon lake breeze; winters are cold, cloudy, and snowy.
Beyond snow, the main concerns are dense lake-driven cloud cover through the cold season, occasional severe thunderstorms in summer, and lakeshore wind and wave action that the marine desk tracks for the Pennsylvania shoreline.
Climate normals (approximate)
- Warmest month: July — average high around 80 °F
- Coldest month: January — average low around 20 °F
- Annual precipitation: roughly 45 inches
- Annual snowfall: about 100 inches (mostly lake-effect)
- Climate type: humid continental (Köppen Dfb)
Common questions
- Why does Erie get so much snow?
- Lake-effect snow. Cold air crossing the relatively warm, open water of Lake Erie picks up moisture and dumps it as heavy, localized snow on the shore — Erie among the snowiest cities in the United States.
- When is lake-effect snow worst?
- From late November into January, before the lake freezes over. Once Lake Erie ices up, the lake-effect machine shuts down for the rest of winter.
- Are Erie's summers hot?
- Usually mild. The lake moderates temperatures, so highs are often in the low 80s with a cooling afternoon lake breeze near the shore.
Figures are long-term climate normals (roughly the 1991–2020 reference period) and are meant for context. The live readings at the top of this page always reflect current conditions.