Frost dates for 99820Angoon, AK
The average last spring frost in Angoon is April 29 and the average first fall frost is October 25, giving a typical growing season of about 176 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 29
- Average first fall frost
- Oct 25
- Growing season
- 176 days
Safer after May 15 (1-in-10 risk)
Possible by Oct 7 (1-in-10 risk)
Last frost typically in 184 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 30 · May 14 · May 29 | Sep 22 · Oct 9 · Oct 25 | 146 days | 100% |
| Frost / freeze (32°F) | Apr 15 · Apr 29 · May 15 | Oct 7 · Oct 25 · Nov 10 | 176 days | 100% |
| Hard freeze (28°F) | Mar 22 · Apr 10 · Apr 29 | Oct 22 · Nov 9 · Dec 1 | 212 days | 100% |
Planting calendar for Angoon
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 29 – Jun 4 |
| Tomatoes | Transplant outdoors | May 15 – Jul 5 |
| Peppers | Start seeds indoors | Mar 29 – Apr 29 |
| Peppers | Transplant outdoors | May 29 – Jun 29 |
| Eggplant | Start seeds indoors | Apr 15 – May 14 |
| Eggplant | Transplant outdoors | May 29 – Jun 29 |
| Cucumbers | Sow outdoors | May 29 – Jul 15 |
| Summer squash | Sow outdoors | May 15 – Jun 29 |
| Winter squash & pumpkins | Sow outdoors | May 29 – Jun 29 |
| Snap beans | Sow outdoors | May 15 – Aug 7 |
| Sweet corn | Sow outdoors | May 15 – Jul 5 |
| Watermelon & cantaloupe | Sow outdoors | May 29 – Jun 29 |
| Okra | Sow outdoors | May 22 – Jun 14 |
| Peas | Sow outdoors (spring) | Mar 29 – May 14 |
| Potatoes | Plant outdoors (spring) | Mar 29 – May 29 |
| Onions | Start seeds indoors (spring) | Feb 15 – Mar 14 |
| Onions | Transplant outdoors (spring) | Apr 15 – May 14 |
| Broccoli | Start seeds indoors (spring) | Mar 11 – Apr 14 |
| Broccoli | Transplant outdoors (spring) | Apr 15 – May 14 |
| Broccoli | Start seeds indoors (fall) | Jun 25 – Jul 5 |
| Broccoli | Transplant outdoors (fall) | Jul 25 – Aug 5 |
| Cabbage | Start seeds indoors (spring) | Mar 1 – Mar 29 |
| Cabbage | Transplant outdoors (spring) | Mar 29 – Apr 29 |
| Cabbage | Start seeds indoors (fall) | Jun 15 – Jul 15 |
| Cabbage | Transplant outdoors (fall) | Jul 15 – Aug 15 |
| Leaf lettuce | Sow outdoors (spring) | Mar 29 – Jun 14 |
| Leaf lettuce | Sow outdoors (fall) | Jul 15 – Aug 31 |
| Spinach | Sow outdoors (spring) | Mar 22 – May 5 |
| Spinach | Sow outdoors (fall) | Aug 1 – Sep 5 |
| Radishes | Sow outdoors (spring) | Mar 29 – May 19 |
| Radishes | Sow outdoors (fall) | Jul 15 – Sep 15 |
| Kale | Sow outdoors (spring) | Apr 15 – May 5 |
| Kale | Sow outdoors (fall) | Jul 8 – Aug 15 |
| Carrots | Sow outdoors (spring) | Apr 29 – Jun 14 |
| Carrots | Sow outdoors (fall) | Jun 15 – Jul 31 |
| Garlic | Plant outdoors (fall) | Oct 15 – Nov 15 |
Where these dates come from
ZIP code 99820 is matched to the NOAA station Hidden Falls Hatchery, AK, 36 km away, at 22 ft elevation (6 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Hidden Falls Hatchery, AK (used) | 22 ft | Apr 29 | Oct 25 |
| Sitka 1 Ne, AK | 78 ft | May 3 | Oct 18 |
| Sitka Airport, AK | 14 ft | Apr 12 | Nov 1 |
| Hoonah, AK | 130 ft | May 9 | Oct 4 |
Frost dates near Angoon
- Tenakee Springs, AK 99841 · last May 9, first Oct 4
- Sitka, AK 99835 · last May 3, first Oct 18
- Kake, AK 99830 · last Apr 29, first Oct 17
- Hoonah, AK 99829 · last May 9, first Oct 4
- Douglas, AK 99824 · last Apr 20, first Oct 22
- Juneau, AK 99802 · last Apr 20, first Oct 22
- Auke Bay, AK 99821 · last May 21, first Oct 1
- Gustavus, AK 99826 · last May 30, first Sep 16
Frequently asked questions
- When is the last frost in Angoon, AK?
- For ZIP code 99820, the average last spring frost (32°F) is April 29, based on NOAA 1991-2020 climate normals for the Hidden Falls Hatchery, AK weather station. There is a 1-in-10 chance of a frost after May 15.
- When is the first frost in Angoon, AK?
- The average first fall frost (32°F) is October 25. 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 99820?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 176 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.