Frost dates for 99667Skwentna, AK
The average last spring frost in Skwentna is May 23 and the average first fall frost is September 9, giving a typical growing season of about 109 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 23
- Average first fall frost
- Sep 9
- Growing season
- 109 days
Safer after Jun 4 (1-in-10 risk)
Possible by Aug 26 (1-in-10 risk)
Last frost typically in 208 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) | May 25 · Jun 5 · Jun 22 | Aug 14 · Aug 30 · Sep 13 | 84 days | 100% |
| Frost / freeze (32°F) | May 8 · May 23 · Jun 4 | Aug 26 · Sep 9 · Sep 25 | 109 days | 100% |
| Hard freeze (28°F) | Apr 24 · May 8 · May 22 | Sep 3 · Sep 23 · Oct 7 | 137 days | 100% |
Planting calendar for Skwentna
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 22 – Jun 28 |
| Tomatoes | Transplant outdoors | Jun 8 – May 20 |
| Peppers | Start seeds indoors | Apr 22 – May 23 |
| Peppers | Transplant outdoors | Jun 22 – Jul 23 |
| Eggplant | Start seeds indoors | May 9 – Jun 7 |
| Eggplant | Transplant outdoors | Jun 22 – Jul 23 |
| Cucumbers | Sow outdoors | Jun 22 – May 30 |
| Summer squash | Sow outdoors | Jun 8 – Jul 23 |
| Winter squash & pumpkins | Sow outdoors | Jun 22 – Jul 23 |
| Snap beans | Sow outdoors | Jun 8 – Jun 22 |
| Sweet corn | Sow outdoors | Jun 8 – May 20 |
| Watermelon & cantaloupe | Sow outdoors | Jun 22 – Jul 23 |
| Okra | Sow outdoors | Jun 15 – Jul 8 |
| Peas | Sow outdoors (spring) | Apr 22 – Jun 7 |
| Potatoes | Plant outdoors (spring) | Apr 22 – Jun 22 |
| Onions | Start seeds indoors (spring) | Mar 11 – Apr 7 |
| Onions | Transplant outdoors (spring) | May 9 – Jun 7 |
| Broccoli | Start seeds indoors (spring) | Apr 4 – May 8 |
| Broccoli | Transplant outdoors (spring) | May 9 – Jun 7 |
| Broccoli | Start seeds indoors (fall) | May 10 – May 20 |
| Broccoli | Transplant outdoors (fall) | Jun 9 – Jun 20 |
| Cabbage | Start seeds indoors (spring) | Mar 25 – Apr 22 |
| Cabbage | Transplant outdoors (spring) | Apr 22 – May 23 |
| Cabbage | Start seeds indoors (fall) | Apr 30 – May 30 |
| Cabbage | Transplant outdoors (fall) | May 30 – Jun 30 |
| Leaf lettuce | Sow outdoors (spring) | Apr 22 – Jul 8 |
| Leaf lettuce | Sow outdoors (fall) | May 30 – Jul 16 |
| Spinach | Sow outdoors (spring) | Apr 15 – May 29 |
| Spinach | Sow outdoors (fall) | Jun 16 – Jul 21 |
| Radishes | Sow outdoors (spring) | Apr 22 – Jun 12 |
| Radishes | Sow outdoors (fall) | May 30 – Jul 31 |
| Kale | Sow outdoors (spring) | May 9 – May 29 |
| Kale | Sow outdoors (fall) | May 23 – Jun 30 |
| Carrots | Sow outdoors (spring) | May 23 – Jul 8 |
| Carrots | Sow outdoors (fall) | Apr 30 – Jun 15 |
| Garlic | Plant outdoors (fall) | Aug 30 – Sep 30 |
Where these dates come from
ZIP code 99667 is matched to the NOAA station Skwentna, AK, 9.6 km away, at 150 ft elevation (21 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Skwentna, AK (used) | 150 ft | May 23 | Sep 9 |
| Hayes River, AK | 1,000 ft | Jun 2 | Sep 8 |
| Amber Lake, AK | 449 ft | May 28 | Sep 13 |
| Puntilla, AK | 1,858 ft | Jun 7 | Sep 2 |
Frost dates near Skwentna
- Trapper Creek, AK 99683 · last May 16, first Sep 16
- Talkeetna, AK 99676 · last May 16, first Sep 16
- Tyonek, AK 99682 · last May 18, first Sep 22
Frequently asked questions
- When is the last frost in Skwentna, AK?
- For ZIP code 99667, the average last spring frost (32°F) is May 23, based on NOAA 1991-2020 climate normals for the Skwentna, AK weather station. There is a 1-in-10 chance of a frost after June 4.
- When is the first frost in Skwentna, AK?
- The average first fall frost (32°F) is September 9. There is a 1-in-10 chance of frost by August 26, so tender plants are at risk from that point on.
- How long is the growing season in 99667?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 109 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.