Frost dates for 15665Manor, PA
The average last spring frost in Manor is May 2 and the average first fall frost is October 20, giving a typical growing season of about 170 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 2
- Average first fall frost
- Oct 20
- Growing season
- 170 days
Safer after May 20 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 180 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 26 · May 12 · May 27 | Sep 21 · Oct 7 · Oct 24 | 149 days | 100% |
| Frost / freeze (32°F) | Apr 17 · May 2 · May 20 | Oct 1 · Oct 20 · Nov 3 | 170 days | 100% |
| Hard freeze (28°F) | Apr 2 · Apr 20 · May 10 | Oct 10 · Nov 1 · Nov 14 | 194 days | 100% |
Planting calendar for Manor
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 | Apr 1 – Jun 7 |
| Tomatoes | Transplant outdoors | May 18 – Jun 30 |
| Peppers | Start seeds indoors | Apr 1 – May 2 |
| Peppers | Transplant outdoors | Jun 1 – Jul 2 |
| Eggplant | Start seeds indoors | Apr 18 – May 17 |
| Eggplant | Transplant outdoors | Jun 1 – Jul 2 |
| Cucumbers | Sow outdoors | Jun 1 – Jul 10 |
| Summer squash | Sow outdoors | May 18 – Jul 2 |
| Winter squash & pumpkins | Sow outdoors | Jun 1 – Jul 2 |
| Snap beans | Sow outdoors | May 18 – Aug 2 |
| Sweet corn | Sow outdoors | May 18 – Jun 30 |
| Watermelon & cantaloupe | Sow outdoors | Jun 1 – Jul 2 |
| Okra | Sow outdoors | May 25 – Jun 17 |
| Peas | Sow outdoors (spring) | Apr 1 – May 17 |
| Potatoes | Plant outdoors (spring) | Apr 1 – Jun 1 |
| Onions | Start seeds indoors (spring) | Feb 18 – Mar 17 |
| Onions | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (spring) | Mar 14 – Apr 17 |
| Broccoli | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (fall) | Jun 20 – Jun 30 |
| Broccoli | Transplant outdoors (fall) | Jul 20 – Jul 31 |
| Cabbage | Start seeds indoors (spring) | Mar 4 – Apr 1 |
| Cabbage | Transplant outdoors (spring) | Apr 1 – May 2 |
| Cabbage | Start seeds indoors (fall) | Jun 10 – Jul 10 |
| Cabbage | Transplant outdoors (fall) | Jul 10 – Aug 10 |
| Leaf lettuce | Sow outdoors (spring) | Apr 1 – Jun 17 |
| Leaf lettuce | Sow outdoors (fall) | Jul 10 – Aug 26 |
| Spinach | Sow outdoors (spring) | Mar 25 – May 8 |
| Spinach | Sow outdoors (fall) | Jul 27 – Aug 31 |
| Radishes | Sow outdoors (spring) | Apr 1 – May 22 |
| Radishes | Sow outdoors (fall) | Jul 10 – Sep 10 |
| Kale | Sow outdoors (spring) | Apr 18 – May 8 |
| Kale | Sow outdoors (fall) | Jul 3 – Aug 10 |
| Carrots | Sow outdoors (spring) | May 2 – Jun 17 |
| Carrots | Sow outdoors (fall) | Jun 10 – Jul 26 |
| Garlic | Plant outdoors (fall) | Oct 10 – Nov 10 |
Where these dates come from
ZIP code 15665 is matched to the NOAA station Mckeesport, PA, 16.1 km away, at 740 ft elevation (195 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Mckeesport, PA (used) | 740 ft | May 2 | Oct 20 |
| Murrysville 2 Sw, PA | 860 ft | Apr 22 | Oct 25 |
| Braddock Lock 2, PA | 730 ft | Apr 5 | Nov 10 |
| Mt Pleasant, PA | 1,003 ft | May 1 | Oct 13 |
Frost dates near Manor
- Westmoreland City, PA 15692 · last May 2, first Oct 14
- Penn, PA 15675 · last May 2, first Oct 14
- Adamsburg, PA 15611 · last Apr 29, first Oct 20
- Harrison City, PA 15636 · last Apr 29, first Oct 20
- Irwin, PA 15642 · last May 2, first Oct 20
- Wendel, PA 15691 · last Apr 29, first Oct 20
- Jeannette, PA 15644 · last May 2, first Oct 14
- Larimer, PA 15647 · last May 2, first Oct 20
Frequently asked questions
- When is the last frost in Manor, PA?
- For ZIP code 15665, the average last spring frost (32°F) is May 2, based on NOAA 1991-2020 climate normals for the Mckeesport, PA weather station. There is a 1-in-10 chance of a frost after May 20.
- When is the first frost in Manor, PA?
- The average first fall frost (32°F) is October 20. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
- How long is the growing season in 15665?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 170 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.