Pennsylvania frost dates
Across 159 weather stations in Pennsylvania, the median last spring frost runs from Mar 30 in Marcus Hook to May 24 in Kane, and the first fall frost from Sep 27 to Nov 17.
Pennsylvania at a glance
- Weather stations
- 159
- Earliest last frost
- Mar 30 Marcus Hook
- Latest last frost
- May 24 Kane
- Longest season
- 232 days Phila Franklin Inst
- Typical season
- about 173 frost-free days
- Hardiness zones
- Zones 5b to 7b
Frost dates by weather station
| Weather station | Last spring frost | First fall frost | Frost-free days | Zone |
|---|---|---|---|---|
| Acmetonia Lock | Apr 16 | Nov 1 | 197 | 6b |
| Allentown International Airport | Apr 20 | Oct 24 | 184 | 7a |
| Altoona 3 mi W | Apr 25 | Oct 21 | 176 | 6b |
| Altoona 7 mi SW | Apr 25 | Oct 20 | 177 | 6b |
| Altoona Blair County Airport | Apr 23 | Oct 21 | 177 | 6b |
| Alvin R Bush Dam | Apr 29 | Oct 21 | 177 | 6a |
| Avondale | Apr 19 | Oct 26 | 189 | 7a |
| Bear Gap | Apr 27 | Oct 20 | 172 | 6b |
| Beaver Falls | Apr 27 | Oct 25 | 178 | 6b |
| Benton | May 4 | Oct 11 | 159 | 6a |
| Biglerville | Apr 15 | Oct 27 | 194 | 7a |
| Bloserville | Apr 18 | Oct 26 | 191 | 7a |
| Blue Marsh Lake | Apr 26 | Oct 19 | 176 | 7a |
| Braddock Lock | Apr 5 | Nov 10 | 219 | 6b |
| Bradford Regional Airport | May 18 | Oct 1 | 136 | 5b |
| Bradford Research | May 18 | Oct 4 | 140 | 5b |
| Bucksville | Apr 29 | Oct 16 | 170 | 6b |
| Butler | May 7 | Oct 14 | 159 | 6b |
| Canton | May 16 | Oct 2 | 139 | 6a |
| Carlisle Water Plant | Apr 23 | Oct 18 | 177 | 7a |
| Cashtown | Apr 28 | Oct 17 | 170 | 7a |
| Chalk Hill | May 19 | Oct 1 | 135 | 6a |
| Chambersburg | Apr 18 | Oct 25 | 188 | 7a |
| Chandlers Valley | May 22 | Sep 30 | 131 | 5b |
| Charleroi Lock | Apr 13 | Nov 5 | 205 | 6b |
| Clarence | May 21 | Sep 27 | 130 | 6a |
| Clarion | May 9 | Oct 11 | 154 | 6a |
| Clearfield Lawrence Airport | May 4 | Oct 11 | 161 | 6a |
| Clermont | May 15 | Oct 3 | 140 | 5b |
| Coatesville | Apr 19 | Oct 25 | 190 | 7a |
| Confluence Dam | Apr 30 | Oct 18 | 171 | 6a |
| Connellsville | Apr 22 | Oct 27 | 187 | 6b |
| Cooksburg | May 13 | Oct 7 | 143 | 6a |
| Coudersport 1 mi SW | May 22 | Oct 1 | 130 | 5b |
| Coudersport 7 mi SE | May 14 | Oct 4 | 143 | 5b |
| Cowanesque Dam | May 9 | Oct 12 | 155 | 6a |
| Dehart Dam | May 1 | Oct 16 | 168 | 6b |
| Donegal | Apr 30 | Oct 17 | 170 | 6a |
| Donora | Apr 27 | Oct 22 | 177 | 6b |
| Doylestown Airport | Apr 13 | Oct 30 | 198 | 7a |
| Dubois Jefferson County Airport | May 6 | Oct 14 | 160 | 6a |
| Dushore | May 14 | Oct 2 | 143 | 6a |
| East Stroudsburg | May 1 | Oct 12 | 163 | 6b |
| Ebensburg Sewage Plant | May 17 | Oct 2 | 136 | 6a |
| Eisenhower Nhs | Apr 24 | Oct 21 | 180 | 7a |
| Emporium | May 7 | Oct 15 | 160 | 5b |
| Emsworth Lock and Dam Ohio River | Apr 24 | Oct 27 | 186 | 6b |
| Erie International Airport | Apr 26 | Nov 4 | 192 | 6b |
| Everett | Apr 27 | Oct 17 | 170 | 6b |
| Ford City Dam | May 4 | Oct 16 | 164 | 6b |
| Francis E Walter Dam | May 7 | Oct 6 | 153 | 6a |
| Franklin | May 2 | Oct 23 | 171 | 6a |
| Glen Hazel Dam | May 14 | Oct 6 | 143 | 5b |
| Glenmoore | Apr 11 | Nov 1 | 205 | 7a |
| Glenwillard Dashields Lock and Dam | Apr 8 | Nov 8 | 212 | 7a |
| Grampian | May 4 | Oct 13 | 160 | 6a |
| Graterford | Apr 24 | Oct 15 | 173 | 7a |
| Grays Landing | Apr 28 | Oct 21 | 175 | 6b |
| Hamburg | Apr 16 | Oct 25 | 189 | 7a |
| Hanover | Apr 24 | Oct 20 | 177 | 6b |
| Harrisburg | Apr 15 | Oct 23 | 189 | 7a |
| Harrisburg Capital City Airport | Apr 9 | Nov 1 | 205 | 7a |
| Hawley | May 10 | Oct 4 | 146 | 6a |
| Hidden Valley | May 2 | Oct 17 | 168 | 6a |
| Hopewell Morgantown | Apr 16 | Oct 27 | 193 | 7a |
| Indiana | May 8 | Oct 13 | 157 | 6b |
| Jamestown | May 4 | Oct 14 | 161 | 6a |
| Johnstown Cambria County Airport | Apr 29 | Oct 21 | 176 | 6b |
| Kane | May 24 | Sep 28 | 126 | 5b |
| Lancaster Airport | Apr 18 | Oct 25 | 186 | 7a |
| Lancaster Filter Plant | Apr 19 | Oct 24 | 186 | 7a |
| Landisville | Apr 30 | Oct 10 | 162 | 7a |
| Laporte | May 6 | Oct 7 | 154 | 6a |
| Laurel Mountain | Apr 26 | Oct 17 | 172 | 6a |
| Laurel Summit | May 6 | Oct 12 | 159 | 6a |
| Laurelton Center | Apr 25 | Oct 19 | 175 | 6b |
| Lebanon | Apr 20 | Oct 25 | 185 | 7a |
| Lehighton | Apr 21 | Oct 23 | 184 | 6b |
| Lewisburg | Apr 26 | Oct 20 | 176 | 6b |
| Lewistown | Apr 21 | Oct 24 | 185 | 7a |
| Linesville | Apr 30 | Oct 23 | 177 | 6a |
| Lock Haven Sewage Plant | Apr 30 | Oct 20 | 173 | 6b |
| Loyalhanna Lake | May 2 | Oct 14 | 163 | 6b |
| Mahanoy City | Apr 30 | Oct 22 | 175 | 6b |
| Marcus Hook | Mar 30 | Nov 16 | 230 | 7b |
| Matamoras | May 2 | Oct 12 | 164 | 6b |
| McKeesport | May 2 | Oct 20 | 170 | 6b |
| Mercer | May 15 | Oct 3 | 140 | 6a |
| Meyersdale | May 12 | Oct 5 | 146 | 6a |
| Middletown Harrisburg International Airport | Apr 9 | Nov 2 | 206 | 7a |
| Milanville | May 3 | Oct 9 | 156 | 6a |
| Millheim | May 5 | Oct 6 | 153 | 6b |
| Montgomery Lock and Dam | Apr 28 | Oct 26 | 178 | 6b |
| Montrose | May 14 | Oct 2 | 141 | 5b |
| Moon Twp | Apr 28 | Oct 18 | 172 | 7a |
| Mount Pleasant | May 1 | Oct 13 | 164 | 6b |
| Mount Pocono Mountains Airport | May 6 | Oct 8 | 154 | 6a |
| Murrysville | Apr 22 | Oct 25 | 186 | 6b |
| Natrona Lock | Apr 16 | Nov 2 | 199 | 6b |
| Neshaminy Falls | Apr 21 | Oct 25 | 185 | 7a |
| New Castle | Apr 30 | Oct 23 | 175 | 6a |
| New Holland | Apr 14 | Nov 1 | 198 | 7a |
| Norristown | Apr 8 | Oct 31 | 203 | 7b |
| Octoraro Lake | Apr 26 | Oct 22 | 179 | 7a |
| Oswayo | May 20 | Sep 29 | 130 | 5b |
| Phila Franklin Inst | Mar 30 | Nov 17 | 232 | 7b |
| Philadelphia International Airport | Apr 2 | Nov 10 | 224 | 7b |
| Philadelphia NE Airport | Apr 4 | Nov 7 | 216 | 7b |
| Philipsburg | May 13 | Oct 1 | 142 | 6a |
| Phoenixville | Apr 18 | Oct 27 | 192 | 7a |
| Pittsburgh Allegheny County Airport | Apr 18 | Oct 28 | 193 | 6b |
| Pittsburgh International Airport | Apr 23 | Oct 23 | 181 | 6b |
| Pleasant Mount | May 14 | Oct 1 | 140 | 5b |
| Point Marion Lock | Apr 30 | Oct 23 | 177 | 6b |
| Port Allegany | May 15 | Oct 6 | 144 | 5b |
| Port Meadville Airport | Apr 30 | Oct 23 | 175 | 6a |
| Pottstown Limerick Airport | Apr 20 | Oct 23 | 186 | 7a |
| Prince Gallitzin State Park | May 10 | Oct 5 | 149 | 6a |
| Putneyville Dam | May 10 | Oct 12 | 155 | 6a |
| Raystown Headquarters | Apr 19 | Oct 29 | 194 | 7a |
| Raystown Lake | Apr 19 | Oct 28 | 191 | 7a |
| Reading | Apr 10 | Oct 31 | 202 | 7a |
| Reading Spaatz Field | Apr 14 | Oct 29 | 197 | 7a |
| Rector | May 5 | Oct 6 | 152 | 6a |
| Renovo | Apr 30 | Oct 22 | 173 | 6a |
| Ridgway | May 13 | Oct 11 | 150 | 5b |
| Rodale Research Center | Apr 26 | Oct 14 | 171 | 6b |
| Safe Harbor Dam | Apr 1 | Nov 10 | 221 | 7a |
| Salina | Apr 29 | Oct 20 | 171 | 6b |
| Schenley Lock | Apr 21 | Oct 30 | 190 | 6b |
| Selinsgrove | Apr 25 | Oct 22 | 178 | 6b |
| Selinsgrove Penn Valley Airport | Apr 27 | Oct 16 | 172 | 6b |
| Sellersville | Apr 26 | Oct 17 | 175 | 7a |
| Shawnee State Park | May 4 | Oct 10 | 158 | 6b |
| Shippensburg | Apr 19 | Oct 24 | 188 | 7a |
| Slippery Rock | May 7 | Oct 14 | 158 | 6a |
| South Mountain | Apr 27 | Oct 20 | 177 | 7a |
| Springboro | May 8 | Oct 16 | 160 | 6a |
| Springtown | Apr 21 | Oct 22 | 184 | 7a |
| State College | Apr 20 | Oct 26 | 187 | 6b |
| Stevenson Dam | May 10 | Oct 16 | 157 | 6a |
| Sunbury | Apr 30 | Oct 13 | 166 | 6b |
| Tioga Hammond Dam | May 6 | Oct 10 | 158 | 6a |
| Tionesta Lake | May 1 | Oct 25 | 176 | 6a |
| Titusville Water Works | May 12 | Oct 10 | 149 | 6a |
| Towanda | May 2 | Oct 15 | 165 | 6a |
| Union City Filtration Plant | May 7 | Oct 10 | 155 | 6a |
| Uniontown | Apr 30 | Oct 18 | 171 | 6b |
| Warren | May 4 | Oct 21 | 168 | 6a |
| Washington | Apr 24 | Oct 23 | 181 | 6b |
| Waynesburg | May 3 | Oct 15 | 164 | 6b |
| Wellsboro | May 10 | Oct 5 | 148 | 6a |
| West Chester | Apr 26 | Oct 18 | 174 | 7a |
| Wilkes-Barre International Airport | Apr 23 | Oct 20 | 178 | 6b |
| Williamsport | Apr 24 | Oct 23 | 180 | 6b |
| Willow Grove Naval Air Station | Apr 11 | Nov 1 | 205 | 7a |
| Wolfsburg | Apr 29 | Oct 13 | 167 | 6b |
| York Airport | Apr 27 | Oct 18 | 174 | 6b |
| York Pump Station | Apr 26 | Oct 19 | 177 | 7a |
Median dates from NOAA 1991–2020 climate normals. How to read them.