Frost dates · Pennsylvania
Pennsylvania frost dates,
county by county.
Last spring frost and first fall frost probability data for all 67 counties in Pennsylvania, computed from the NOAA 1991–2020 Climate Normals. Every county page surfaces the full probability table at three temperature thresholds plus crop-specific planting guidance.
Variation across Pennsylvania
52 days separate the earliest and latest counties.
The median last spring frost in Philadelphia County is March 17 — 52 days earlier than Warren County at May 8. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.
By frost timing
Counties sorted by last spring frost.
Latest at top, earliest at bottom. In most states this matches the north-to-south gradient.
- Warren CountySpring May 8·Fall Oct 11156-day season
- Cambria CountySpring May 4·Fall Oct 13162-day season
- McKean CountySpring May 3·Fall Oct 14164-day season
- Mercer CountySpring May 3·Fall Oct 13163-day season
- Wayne CountySpring May 3·Fall Oct 12162-day season
- Potter CountySpring May 2·Fall Oct 17168-day season
- Susquehanna CountySpring May 2·Fall Oct 15166-day season
- Elk CountySpring May 1·Fall Oct 25177-day season
- Clarion CountySpring Apr 29·Fall Oct 24178-day season
- Pike CountySpring Apr 29·Fall Oct 16170-day season
- Tioga CountySpring Apr 28·Fall Oct 17172-day season
- Cameron CountySpring Apr 27·Fall Oct 28184-day season
- Indiana CountySpring Apr 27·Fall Oct 25181-day season
- Sullivan CountySpring Apr 27·Fall Oct 20176-day season
- Butler CountySpring Apr 26·Fall Oct 27184-day season
- Monroe CountySpring Apr 25·Fall Oct 21179-day season
- Jefferson CountySpring Apr 24·Fall Oct 28187-day season
- Luzerne CountySpring Apr 24·Fall Oct 19178-day season
- Armstrong CountySpring Apr 23·Fall Oct 28188-day season
- Clearfield CountySpring Apr 23·Fall Oct 27187-day season
- Columbia CountySpring Apr 22·Fall Oct 24185-day season
- Greene CountySpring Apr 22·Fall Oct 25186-day season
- Somerset CountySpring Apr 22·Fall Oct 28189-day season
- Bradford CountySpring Apr 21·Fall Oct 30192-day season
- Venango CountySpring Apr 21·Fall Nov 3196-day season
- Forest CountySpring Apr 20·Fall Nov 4198-day season
- Lawrence CountySpring Apr 20·Fall Nov 2196-day season
- Westmoreland CountySpring Apr 20·Fall Oct 24187-day season
- Clinton CountySpring Apr 18·Fall Nov 2198-day season
- Crawford CountySpring Apr 18·Fall Nov 4200-day season
- Dauphin CountySpring Apr 18·Fall Oct 30195-day season
- Beaver CountySpring Apr 17·Fall Nov 4201-day season
- Fayette CountySpring Apr 17·Fall Oct 28194-day season
- Schuylkill CountySpring Apr 16·Fall Nov 1199-day season
- Montour CountySpring Apr 14·Fall Nov 1201-day season
- Northumberland CountySpring Apr 14·Fall Oct 26195-day season
- Bedford CountySpring Apr 13·Fall Oct 27197-day season
- Allegheny CountySpring Apr 12·Fall Nov 5207-day season
- Blair CountySpring Apr 12·Fall Nov 1203-day season
- Fulton CountySpring Apr 12·Fall Oct 29200-day season
- Union CountySpring Apr 12·Fall Nov 2204-day season
- Erie CountySpring Apr 11·Fall Nov 16219-day season
- Washington CountySpring Apr 11·Fall Nov 2205-day season
- Cumberland CountySpring Apr 10·Fall Nov 1205-day season
- Lackawanna CountySpring Apr 10·Fall Nov 3207-day season
- Lycoming CountySpring Apr 10·Fall Nov 4208-day season
- Montgomery CountySpring Apr 10·Fall Oct 27200-day season
- Snyder CountySpring Apr 10·Fall Nov 1205-day season
- Wyoming CountySpring Apr 10·Fall Nov 3207-day season
- Centre CountySpring Apr 8·Fall Nov 5211-day season
- York CountySpring Apr 8·Fall Oct 31206-day season
- Adams CountySpring Apr 7·Fall Nov 1208-day season
- Carbon CountySpring Apr 7·Fall Nov 4211-day season
- Huntingdon CountySpring Apr 6·Fall Nov 9217-day season
- Juniata CountySpring Apr 6·Fall Nov 5213-day season
- Mifflin CountySpring Apr 6·Fall Nov 5213-day season
- Lancaster CountySpring Apr 5·Fall Nov 4213-day season
- Lehigh CountySpring Apr 5·Fall Nov 4213-day season
- Franklin CountySpring Apr 4·Fall Nov 6216-day season
- Lebanon CountySpring Apr 4·Fall Nov 5215-day season
- Northampton CountySpring Apr 4·Fall Nov 4214-day season
- Chester CountySpring Apr 3·Fall Nov 6217-day season
- Perry CountySpring Apr 3·Fall Nov 9220-day season
- Bucks CountySpring Apr 2·Fall Nov 10222-day season
- Berks CountySpring Mar 30·Fall Nov 11226-day season
- Delaware CountySpring Mar 20·Fall Nov 28253-day season
- Philadelphia CountySpring Mar 17·Fall Nov 29257-day season
Alphabetical
All Pennsylvania counties — A to Z.
- Adams County
- Allegheny County
- Armstrong County
- Beaver County
- Bedford County
- Berks County
- Blair County
- Bradford County
- Bucks County
- Butler County
- Cambria County
- Cameron County
- Carbon County
- Centre County
- Chester County
- Clarion County
- Clearfield County
- Clinton County
- Columbia County
- Crawford County
- Cumberland County
- Dauphin County
- Delaware County
- Elk County
- Erie County
- Fayette County
- Forest County
- Franklin County
- Fulton County
- Greene County
- Huntingdon County
- Indiana County
- Jefferson County
- Juniata County
- Lackawanna County
- Lancaster County
- Lawrence County
- Lebanon County
- Lehigh County
- Luzerne County
- Lycoming County
- McKean County
- Mercer County
- Mifflin County
- Monroe County
- Montgomery County
- Montour County
- Northampton County
- Northumberland County
- Perry County
- Philadelphia County
- Pike County
- Potter County
- Schuylkill County
- Snyder County
- Somerset County
- Sullivan County
- Susquehanna County
- Tioga County
- Union County
- Venango County
- Warren County
- Washington County
- Wayne County
- Westmoreland County
- Wyoming County
- York County