Last frost date in St. Marys, Pennsylvania
May 14
Average last frost in spring. In an early year (1 in 10) it's over by April 28; in a late year (1 in 10) it comes after May 29.
October 6
Average first frost in fall. 1 year in 10 it comes by September 24.
Source: NOAA U.S. Climate Normals 1991–2020, station Glen Hazel 2 NE Dam (USC00363311), 8.4 miles from St. Marys, elevation 1,720 ft. NOAA National Centers for Environmental Information. These are long-term averages, not a forecast.
| Early year | Average | Late year | |
|---|---|---|---|
| Last frost in spring | Apr 28 | May 14 | May 29 |
| First frost in fall | Sept 24 | Oct 6 | Oct 20 |
Frost-free days in an average year: 143
| Chance in a year | Average last in spring | Average first in fall | |
|---|---|---|---|
| Light frost (36°F) | Every year | May 27 | Sept 27 |
| Frost (32°F) | Every year | May 14 | Oct 6 |
| Hard freeze (28°F) | Every year | May 3 | Oct 18 |
Nights at 32°F or colder in an average year: 163
What to plant now in St. Marys
- Spring planting calendar for an average last frost around May 10 St. Marys: May 14
- Fall planting calendar for an average first frost around October 10 St. Marys: October 6
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), “Suburban and Farm Vegetable Gardens,” tables 4 and 5. How we match the table.
Nearby in Pennsylvania
- State College 57 mi · last frost Apr 20
- Altoona 66 mi · last frost Apr 25
- Indiana 66 mi · last frost May 8
- Williamsport 78 mi · last frost Apr 25
- Johnstown 81 mi · last frost Apr 29