Frost dates for 18071Palmerton, PA
The average last spring frost in Palmerton is April 21 and the average first fall frost is October 23, giving a typical growing season of about 184 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 21
- Average first fall frost
- Oct 23
- Growing season
- 184 days
Safer after May 9 (1-in-10 risk)
Possible by Oct 7 (1-in-10 risk)
Last frost typically in 169 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 19 · May 3 · May 20 | Oct 1 · Oct 11 · Oct 25 | 159 days | 100% |
| Frost / freeze (32°F) | Apr 7 · Apr 21 · May 9 | Oct 7 · Oct 23 · Nov 6 | 184 days | 100% |
| Hard freeze (28°F) | Mar 24 · Apr 7 · Apr 22 | Oct 20 · Nov 4 · Nov 19 | 211 days | 100% |
Planting calendar for Palmerton
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 21 – May 27 |
| Tomatoes | Transplant outdoors | May 7 – Jul 3 |
| Peppers | Start seeds indoors | Mar 21 – Apr 21 |
| Peppers | Transplant outdoors | May 21 – Jun 21 |
| Eggplant | Start seeds indoors | Apr 7 – May 6 |
| Eggplant | Transplant outdoors | May 21 – Jun 21 |
| Cucumbers | Sow outdoors | May 21 – Jul 13 |
| Summer squash | Sow outdoors | May 7 – Jun 21 |
| Winter squash & pumpkins | Sow outdoors | May 21 – Jun 21 |
| Snap beans | Sow outdoors | May 7 – Aug 5 |
| Sweet corn | Sow outdoors | May 7 – Jul 3 |
| Watermelon & cantaloupe | Sow outdoors | May 21 – Jun 21 |
| Okra | Sow outdoors | May 14 – Jun 6 |
| Peas | Sow outdoors (spring) | Mar 21 – May 6 |
| Potatoes | Plant outdoors (spring) | Mar 21 – May 21 |
| Onions | Start seeds indoors (spring) | Feb 7 – Mar 6 |
| Onions | Transplant outdoors (spring) | Apr 7 – May 6 |
| Broccoli | Start seeds indoors (spring) | Mar 3 – Apr 6 |
| Broccoli | Transplant outdoors (spring) | Apr 7 – May 6 |
| Broccoli | Start seeds indoors (fall) | Jun 23 – Jul 3 |
| Broccoli | Transplant outdoors (fall) | Jul 23 – Aug 3 |
| Cabbage | Start seeds indoors (spring) | Feb 21 – Mar 21 |
| Cabbage | Transplant outdoors (spring) | Mar 21 – Apr 21 |
| Cabbage | Start seeds indoors (fall) | Jun 13 – Jul 13 |
| Cabbage | Transplant outdoors (fall) | Jul 13 – Aug 13 |
| Leaf lettuce | Sow outdoors (spring) | Mar 21 – Jun 6 |
| Leaf lettuce | Sow outdoors (fall) | Jul 13 – Aug 29 |
| Spinach | Sow outdoors (spring) | Mar 14 – Apr 27 |
| Spinach | Sow outdoors (fall) | Jul 30 – Sep 3 |
| Radishes | Sow outdoors (spring) | Mar 21 – May 11 |
| Radishes | Sow outdoors (fall) | Jul 13 – Sep 13 |
| Kale | Sow outdoors (spring) | Apr 7 – Apr 27 |
| Kale | Sow outdoors (fall) | Jul 6 – Aug 13 |
| Carrots | Sow outdoors (spring) | Apr 21 – Jun 6 |
| Carrots | Sow outdoors (fall) | Jun 13 – Jul 29 |
| Garlic | Plant outdoors (fall) | Oct 13 – Nov 13 |
Where these dates come from
ZIP code 18071 is matched to the NOAA station Lehighton 1Ssw, PA, 8 km away, at 455 ft elevation (83 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Lehighton 1Ssw, PA (used) | 455 ft | Apr 21 | Oct 23 |
| Allentown Intl Ap, PA | 390 ft | Apr 20 | Oct 24 |
| Rodale Rsch Ctr, PA | 550 ft | Apr 26 | Oct 14 |
| Francis E Walter Dam, PA | 1,509 ft | May 7 | Oct 6 |
Frost dates near Palmerton
- Aquashicola, PA 18012 · last Apr 20, first Oct 24
- Bowmanstown, PA 18030 · last Apr 21, first Oct 23
- Parryville, PA 18244 · last Apr 21, first Oct 23
- Walnutport, PA 18088 · last Apr 20, first Oct 24
- Danielsville, PA 18038 · last Apr 20, first Oct 24
- Lehighton, PA 18235 · last Apr 21, first Oct 23
- Cherryville, PA 18035 · last Apr 20, first Oct 24
- Slatington, PA 18080 · last Apr 26, first Oct 14
Frequently asked questions
- When is the last frost in Palmerton, PA?
- For ZIP code 18071, the average last spring frost (32°F) is April 21, based on NOAA 1991-2020 climate normals for the Lehighton 1Ssw, PA weather station. There is a 1-in-10 chance of a frost after May 9.
- When is the first frost in Palmerton, PA?
- The average first fall frost (32°F) is October 23. There is a 1-in-10 chance of frost by October 7, so tender plants are at risk from that point on.
- How long is the growing season in 18071?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 184 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.