Frost dates for 15676Pleasant Unity, PA
The average last spring frost in Pleasant Unity is May 1 and the average first fall frost is October 13, giving a typical growing season of about 164 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 1
- Average first fall frost
- Oct 13
- Growing season
- 164 days
Safer after May 19 (1-in-10 risk)
Possible by Oct 3 (1-in-10 risk)
Last frost typically in 179 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 28 · May 13 · May 29 | Sep 21 · Oct 3 · Oct 14 | 143 days | 100% |
| Frost / freeze (32°F) | Apr 17 · May 1 · May 19 | Oct 3 · Oct 13 · Oct 26 | 164 days | 100% |
| Hard freeze (28°F) | Apr 6 · Apr 20 · May 8 | Oct 10 · Oct 24 · Nov 8 | 186 days | 100% |
Planting calendar for Pleasant Unity
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 31 – Jun 6 |
| Tomatoes | Transplant outdoors | May 17 – Jun 23 |
| Peppers | Start seeds indoors | Mar 31 – May 1 |
| Peppers | Transplant outdoors | May 31 – Jul 1 |
| Eggplant | Start seeds indoors | Apr 17 – May 16 |
| Eggplant | Transplant outdoors | May 31 – Jul 1 |
| Cucumbers | Sow outdoors | May 31 – Jul 3 |
| Summer squash | Sow outdoors | May 17 – Jul 1 |
| Winter squash & pumpkins | Sow outdoors | May 31 – Jul 1 |
| Snap beans | Sow outdoors | May 17 – Jul 26 |
| Sweet corn | Sow outdoors | May 17 – Jun 23 |
| Watermelon & cantaloupe | Sow outdoors | May 31 – Jul 1 |
| Okra | Sow outdoors | May 24 – Jun 16 |
| Peas | Sow outdoors (spring) | Mar 31 – May 16 |
| Potatoes | Plant outdoors (spring) | Mar 31 – May 31 |
| Onions | Start seeds indoors (spring) | Feb 17 – Mar 16 |
| Onions | Transplant outdoors (spring) | Apr 17 – May 16 |
| Broccoli | Start seeds indoors (spring) | Mar 13 – Apr 16 |
| Broccoli | Transplant outdoors (spring) | Apr 17 – May 16 |
| Broccoli | Start seeds indoors (fall) | Jun 13 – Jun 23 |
| Broccoli | Transplant outdoors (fall) | Jul 13 – Jul 24 |
| Cabbage | Start seeds indoors (spring) | Mar 3 – Mar 31 |
| Cabbage | Transplant outdoors (spring) | Mar 31 – May 1 |
| Cabbage | Start seeds indoors (fall) | Jun 3 – Jul 3 |
| Cabbage | Transplant outdoors (fall) | Jul 3 – Aug 3 |
| Leaf lettuce | Sow outdoors (spring) | Mar 31 – Jun 16 |
| Leaf lettuce | Sow outdoors (fall) | Jul 3 – Aug 19 |
| Spinach | Sow outdoors (spring) | Mar 24 – May 7 |
| Spinach | Sow outdoors (fall) | Jul 20 – Aug 24 |
| Radishes | Sow outdoors (spring) | Mar 31 – May 21 |
| Radishes | Sow outdoors (fall) | Jul 3 – Sep 3 |
| Kale | Sow outdoors (spring) | Apr 17 – May 7 |
| Kale | Sow outdoors (fall) | Jun 26 – Aug 3 |
| Carrots | Sow outdoors (spring) | May 1 – Jun 16 |
| Carrots | Sow outdoors (fall) | Jun 3 – Jul 19 |
| Garlic | Plant outdoors (fall) | Oct 3 – Nov 3 |
Where these dates come from
ZIP code 15676 is matched to the NOAA station Mt Pleasant, PA, 4.9 km away, at 1,003 ft elevation (218 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Mt Pleasant, PA (used) | 1,003 ft | May 1 | Oct 13 |
| Donegal 2 Nw, PA | 1,800 ft | Apr 30 | Oct 17 |
| Rector 3 Ssw, PA | 1,330 ft | May 5 | Oct 6 |
| Laurel Mtn, PA | 2,760 ft | Apr 26 | Oct 17 |
Frost dates near Pleasant Unity
- United, PA 15689 · last May 1, first Oct 13
- Whitney, PA 15693 · last May 2, first Oct 14
- Norvelt, PA 15674 · last May 1, first Oct 13
- Calumet, PA 15621 · last May 1, first Oct 13
- Hostetter, PA 15638 · last May 2, first Oct 14
- Latrobe, PA 15650 · last May 2, first Oct 14
- Armbrust, PA 15616 · last May 1, first Oct 13
- Youngstown, PA 15696 · last May 2, first Oct 14
Frequently asked questions
- When is the last frost in Pleasant Unity, PA?
- For ZIP code 15676, the average last spring frost (32°F) is May 1, based on NOAA 1991-2020 climate normals for the Mt Pleasant, PA weather station. There is a 1-in-10 chance of a frost after May 19.
- When is the first frost in Pleasant Unity, PA?
- The average first fall frost (32°F) is October 13. There is a 1-in-10 chance of frost by October 3, so tender plants are at risk from that point on.
- How long is the growing season in 15676?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 164 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.