Frost dates for 99550Port Lions, AK
The average last spring frost in Port Lions is May 9 and the average first fall frost is October 4, giving a typical growing season of about 148 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 9
- Average first fall frost
- Oct 4
- Growing season
- 148 days
Safer after May 23 (1-in-10 risk)
Possible by Sep 22 (1-in-10 risk)
Last frost typically in 194 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 15 · May 28 · Jun 9 | Sep 9 · Sep 22 · Oct 4 | 116 days | 100% |
| Frost / freeze (32°F) | Apr 22 · May 9 · May 23 | Sep 22 · Oct 4 · Oct 20 | 148 days | 100% |
| Hard freeze (28°F) | Apr 5 · Apr 18 · May 6 | Oct 1 · Oct 19 · Nov 5 | 183 days | 100% |
Planting calendar for Port Lions
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 8 – Jun 14 |
| Tomatoes | Transplant outdoors | May 25 – Jun 14 |
| Peppers | Start seeds indoors | Apr 8 – May 9 |
| Peppers | Transplant outdoors | Jun 8 – Jul 9 |
| Eggplant | Start seeds indoors | Apr 25 – May 24 |
| Eggplant | Transplant outdoors | Jun 8 – Jul 9 |
| Cucumbers | Sow outdoors | Jun 8 – Jun 24 |
| Summer squash | Sow outdoors | May 25 – Jul 9 |
| Winter squash & pumpkins | Sow outdoors | Jun 8 – Jul 9 |
| Snap beans | Sow outdoors | May 25 – Jul 17 |
| Sweet corn | Sow outdoors | May 25 – Jun 14 |
| Watermelon & cantaloupe | Sow outdoors | Jun 8 – Jul 9 |
| Okra | Sow outdoors | Jun 1 – Jun 24 |
| Peas | Sow outdoors (spring) | Apr 8 – May 24 |
| Potatoes | Plant outdoors (spring) | Apr 8 – Jun 8 |
| Onions | Start seeds indoors (spring) | Feb 25 – Mar 24 |
| Onions | Transplant outdoors (spring) | Apr 25 – May 24 |
| Broccoli | Start seeds indoors (spring) | Mar 21 – Apr 24 |
| Broccoli | Transplant outdoors (spring) | Apr 25 – May 24 |
| Broccoli | Start seeds indoors (fall) | Jun 4 – Jun 14 |
| Broccoli | Transplant outdoors (fall) | Jul 4 – Jul 15 |
| Cabbage | Start seeds indoors (spring) | Mar 11 – Apr 8 |
| Cabbage | Transplant outdoors (spring) | Apr 8 – May 9 |
| Cabbage | Start seeds indoors (fall) | May 25 – Jun 24 |
| Cabbage | Transplant outdoors (fall) | Jun 24 – Jul 25 |
| Leaf lettuce | Sow outdoors (spring) | Apr 8 – Jun 24 |
| Leaf lettuce | Sow outdoors (fall) | Jun 24 – Aug 10 |
| Spinach | Sow outdoors (spring) | Apr 1 – May 15 |
| Spinach | Sow outdoors (fall) | Jul 11 – Aug 15 |
| Radishes | Sow outdoors (spring) | Apr 8 – May 29 |
| Radishes | Sow outdoors (fall) | Jun 24 – Aug 25 |
| Kale | Sow outdoors (spring) | Apr 25 – May 15 |
| Kale | Sow outdoors (fall) | Jun 17 – Jul 25 |
| Carrots | Sow outdoors (spring) | May 9 – Jun 24 |
| Carrots | Sow outdoors (fall) | May 25 – Jul 10 |
| Garlic | Plant outdoors (fall) | Sep 24 – Oct 25 |
Where these dates come from
ZIP code 99550 is matched to the NOAA station Ouzinkie, AK, 23.4 km away, at 40 ft elevation (32 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Ouzinkie, AK (used) | 40 ft | May 9 | Oct 4 |
| Monashka Creek Dam, AK | 130 ft | May 27 | Sep 23 |
| Kodiak Ap, AK | 80 ft | May 5 | Oct 3 |
| Kodiak Wwtp, AK | 54 ft | Apr 29 | Oct 14 |
Frost dates near Port Lions
- Ouzinkie, AK 99644 · last May 9, first Oct 4
- Kodiak, AK 99619 · last Apr 29, first Oct 14
- Larsen Bay, AK 99624 · last May 5, first Oct 3
- Old Harbor, AK 99643 · last May 5, first Oct 3
Frequently asked questions
- When is the last frost in Port Lions, AK?
- For ZIP code 99550, the average last spring frost (32°F) is May 9, based on NOAA 1991-2020 climate normals for the Ouzinkie, AK weather station. There is a 1-in-10 chance of a frost after May 23.
- When is the first frost in Port Lions, AK?
- The average first fall frost (32°F) is October 4. There is a 1-in-10 chance of frost by September 22, so tender plants are at risk from that point on.
- How long is the growing season in 99550?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 148 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.