Frost dates for 16679Six Mile Run, PA
The average last spring frost in Six Mile Run is April 23 and the average first fall frost is October 21, giving a typical growing season of about 177 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 23
- Average first fall frost
- Oct 21
- Growing season
- 177 days
Safer after May 11 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 171 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 21 · May 4 · May 22 | Sep 24 · Oct 7 · Oct 23 | 155 days | 100% |
| Frost / freeze (32°F) | Apr 8 · Apr 23 · May 11 | Oct 5 · Oct 21 · Nov 4 | 177 days | 100% |
| Hard freeze (28°F) | Mar 28 · Apr 11 · Apr 29 | Oct 19 · Nov 1 · Nov 18 | 203 days | 100% |
Planting calendar for Six Mile Run
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 23 – May 29 |
| Tomatoes | Transplant outdoors | May 9 – Jul 1 |
| Peppers | Start seeds indoors | Mar 23 – Apr 23 |
| Peppers | Transplant outdoors | May 23 – Jun 23 |
| Eggplant | Start seeds indoors | Apr 9 – May 8 |
| Eggplant | Transplant outdoors | May 23 – Jun 23 |
| Cucumbers | Sow outdoors | May 23 – Jul 11 |
| Summer squash | Sow outdoors | May 9 – Jun 23 |
| Winter squash & pumpkins | Sow outdoors | May 23 – Jun 23 |
| Snap beans | Sow outdoors | May 9 – Aug 3 |
| Sweet corn | Sow outdoors | May 9 – Jul 1 |
| Watermelon & cantaloupe | Sow outdoors | May 23 – Jun 23 |
| Okra | Sow outdoors | May 16 – Jun 8 |
| Peas | Sow outdoors (spring) | Mar 23 – May 8 |
| Potatoes | Plant outdoors (spring) | Mar 23 – May 23 |
| Onions | Start seeds indoors (spring) | Feb 9 – Mar 8 |
| Onions | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (spring) | Mar 5 – Apr 8 |
| Broccoli | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (fall) | Jun 21 – Jul 1 |
| Broccoli | Transplant outdoors (fall) | Jul 21 – Aug 1 |
| Cabbage | Start seeds indoors (spring) | Feb 23 – Mar 23 |
| Cabbage | Transplant outdoors (spring) | Mar 23 – Apr 23 |
| Cabbage | Start seeds indoors (fall) | Jun 11 – Jul 11 |
| Cabbage | Transplant outdoors (fall) | Jul 11 – Aug 11 |
| Leaf lettuce | Sow outdoors (spring) | Mar 23 – Jun 8 |
| Leaf lettuce | Sow outdoors (fall) | Jul 11 – Aug 27 |
| Spinach | Sow outdoors (spring) | Mar 16 – Apr 29 |
| Spinach | Sow outdoors (fall) | Jul 28 – Sep 1 |
| Radishes | Sow outdoors (spring) | Mar 23 – May 13 |
| Radishes | Sow outdoors (fall) | Jul 11 – Sep 11 |
| Kale | Sow outdoors (spring) | Apr 9 – Apr 29 |
| Kale | Sow outdoors (fall) | Jul 4 – Aug 11 |
| Carrots | Sow outdoors (spring) | Apr 23 – Jun 8 |
| Carrots | Sow outdoors (fall) | Jun 11 – Jul 27 |
| Garlic | Plant outdoors (fall) | Oct 11 – Nov 11 |
Where these dates come from
ZIP code 16679 is matched to the NOAA station Altoona Blair Co Ap, PA, 18 km away, at 1,480 ft elevation (302 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Altoona Blair Co Ap, PA (used) | 1,480 ft | Apr 23 | Oct 21 |
| Everett, PA | 1,000 ft | Apr 27 | Oct 17 |
| Raystown Lake 2, PA | 1,000 ft | Apr 19 | Oct 28 |
| Raystown Hq, PA | 995 ft | Apr 19 | Oct 29 |
Frost dates near Six Mile Run
- Defiance, PA 16633 · last Apr 27, first Oct 17
- Riddlesburg, PA 16672 · last Apr 27, first Oct 17
- Dudley, PA 16634 · last Apr 23, first Oct 21
- Wood, PA 16694 · last Apr 23, first Oct 21
- Broad Top, PA 16621 · last Apr 23, first Oct 21
- Saxton, PA 16678 · last Apr 19, first Oct 28
- Wells Tannery, PA 16691 · last Apr 23, first Oct 21
- Robertsdale, PA 16674 · last Apr 23, first Oct 21
Frequently asked questions
- When is the last frost in Six Mile Run, PA?
- For ZIP code 16679, the average last spring frost (32°F) is April 23, based on NOAA 1991-2020 climate normals for the Altoona Blair Co Ap, PA weather station. There is a 1-in-10 chance of a frost after May 11.
- When is the first frost in Six Mile Run, PA?
- The average first fall frost (32°F) is October 21. There is a 1-in-10 chance of frost by October 5, so tender plants are at risk from that point on.
- How long is the growing season in 16679?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 177 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.