Frost dates for 99121Danville, WA
The average last spring frost in Danville is May 30 and the average first fall frost is September 10, giving a typical growing season of about 102 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 30
- Average first fall frost
- Sep 10
- Growing season
- 102 days
Safer after Jun 17 (1-in-10 risk)
Possible by Aug 28 (1-in-10 risk)
Last frost typically in 216 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) | — | — | 66 days | 100% |
| Frost / freeze (32°F) | May 11 · May 30 · Jun 17 | Aug 28 · Sep 10 · Sep 25 | 102 days | 100% |
| Hard freeze (28°F) | Apr 27 · May 12 · May 28 | Sep 11 · Sep 24 · Oct 5 | 135 days | 100% |
Planting calendar for Danville
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 29 – Jul 5 |
| Tomatoes | Transplant outdoors | Jun 15 – May 21 |
| Peppers | Start seeds indoors | Apr 29 – May 30 |
| Peppers | Transplant outdoors | Jun 29 – Jul 30 |
| Eggplant | Start seeds indoors | May 16 – Jun 14 |
| Eggplant | Transplant outdoors | Jun 29 – Jul 30 |
| Cucumbers | Sow outdoors | Jun 29 – May 31 |
| Summer squash | Sow outdoors | Jun 15 – Jul 30 |
| Winter squash & pumpkins | Sow outdoors | Jun 29 – Jul 30 |
| Snap beans | Sow outdoors | Jun 15 – Jun 23 |
| Sweet corn | Sow outdoors | Jun 15 – May 21 |
| Watermelon & cantaloupe | Sow outdoors | Jun 29 – Jul 30 |
| Okra | Sow outdoors | Jun 22 – Jul 15 |
| Peas | Sow outdoors (spring) | Apr 29 – Jun 14 |
| Potatoes | Plant outdoors (spring) | Apr 29 – Jun 29 |
| Onions | Start seeds indoors (spring) | Mar 18 – Apr 14 |
| Onions | Transplant outdoors (spring) | May 16 – Jun 14 |
| Broccoli | Start seeds indoors (spring) | Apr 11 – May 15 |
| Broccoli | Transplant outdoors (spring) | May 16 – Jun 14 |
| Broccoli | Start seeds indoors (fall) | May 11 – May 21 |
| Broccoli | Transplant outdoors (fall) | Jun 10 – Jun 21 |
| Cabbage | Start seeds indoors (spring) | Apr 1 – Apr 29 |
| Cabbage | Transplant outdoors (spring) | Apr 29 – May 30 |
| Cabbage | Start seeds indoors (fall) | May 1 – May 31 |
| Cabbage | Transplant outdoors (fall) | May 31 – Jul 1 |
| Leaf lettuce | Sow outdoors (spring) | Apr 29 – Jul 15 |
| Leaf lettuce | Sow outdoors (fall) | May 31 – Jul 17 |
| Spinach | Sow outdoors (spring) | Apr 22 – Jun 5 |
| Spinach | Sow outdoors (fall) | Jun 17 – Jul 22 |
| Radishes | Sow outdoors (spring) | Apr 29 – Jun 19 |
| Radishes | Sow outdoors (fall) | May 31 – Aug 1 |
| Kale | Sow outdoors (spring) | May 16 – Jun 5 |
| Kale | Sow outdoors (fall) | May 24 – Jul 1 |
| Carrots | Sow outdoors (spring) | May 30 – Jul 15 |
| Carrots | Sow outdoors (fall) | May 1 – Jun 16 |
| Garlic | Plant outdoors (fall) | Aug 31 – Oct 1 |
Where these dates come from
ZIP code 99121 is matched to the NOAA station Republic, WA, 40.6 km away, at 2,555 ft elevation (147 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Republic, WA (used) | 2,555 ft | May 30 | Sep 10 |
| Northport, WA | 1,497 ft | May 8 | Oct 1 |
| Tonasket 11Ne, WA | 3,434 ft | May 6 | Oct 6 |
| Colville, WA | 1,554 ft | May 2 | Oct 2 |
Frost dates near Danville
- Curlew, WA 99118 · last May 6, first Oct 6
- Laurier, WA 99146 · last May 8, first Oct 1
- Malo, WA 99150 · last May 30, first Sep 10
- Orient, WA 99160 · last May 8, first Oct 1
- Boyds, WA 99107 · last May 8, first Oct 1
- Republic, WA 99166 · last May 30, first Sep 10
- Wauconda, WA 98859 · last May 6, first Oct 6
- Evans, WA 99126 · last May 2, first Oct 2
Frequently asked questions
- When is the last frost in Danville, WA?
- For ZIP code 99121, the average last spring frost (32°F) is May 30, based on NOAA 1991-2020 climate normals for the Republic, WA weather station. There is a 1-in-10 chance of a frost after June 17.
- When is the first frost in Danville, WA?
- The average first fall frost (32°F) is September 10. There is a 1-in-10 chance of frost by August 28, so tender plants are at risk from that point on.
- How long is the growing season in 99121?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 102 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.