Frost dates in Williamsport, PA
The average last spring frost in Williamsport is around April 29 and the first fall frost is around October 23. That gives Williamsport an average growing season of about 177 days.
Last spring frost
| Early (10% chance after) | April 14 |
|---|---|
| Average (50%) | April 29 |
| Late (90%) | May 18 |
First fall frost
| Early (10%) | October 9 |
|---|---|
| Average (50%) | October 23 |
| Late (90% chance before) | November 4 |