Frost dates for 98811Ardenvoir, WA
The average last spring frost in Ardenvoir is April 5 and the average first fall frost is October 24, giving a typical growing season of about 200 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 5
- Average first fall frost
- Oct 24
- Growing season
- 200 days
Safer after May 2 (1-in-10 risk)
Possible by Sep 29 (1-in-10 risk)
Last frost typically in 156 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 14 · May 2 · Jun 3 | Sep 16 · Oct 12 · Oct 27 | 160 days | 100% |
| Frost / freeze (32°F) | Mar 17 · Apr 5 · May 2 | Sep 29 · Oct 24 · Nov 10 | 200 days | 100% |
| Hard freeze (28°F) | Feb 26 · Mar 13 · Apr 4 | Oct 17 · Nov 7 · Nov 25 | 236 days | 100% |
Planting calendar for Ardenvoir
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 5 – May 11 |
| Tomatoes | Transplant outdoors | Apr 21 – Jul 4 |
| Peppers | Start seeds indoors | Mar 5 – Apr 5 |
| Peppers | Transplant outdoors | May 5 – Jun 5 |
| Eggplant | Start seeds indoors | Mar 22 – Apr 20 |
| Eggplant | Transplant outdoors | May 5 – Jun 5 |
| Cucumbers | Sow outdoors | May 5 – Jul 14 |
| Summer squash | Sow outdoors | Apr 21 – Jun 5 |
| Winter squash & pumpkins | Sow outdoors | May 5 – Jun 5 |
| Snap beans | Sow outdoors | Apr 21 – Aug 6 |
| Sweet corn | Sow outdoors | Apr 21 – Jul 4 |
| Watermelon & cantaloupe | Sow outdoors | May 5 – Jun 5 |
| Okra | Sow outdoors | Apr 28 – May 21 |
| Peas | Sow outdoors (spring) | Mar 5 – Apr 20 |
| Potatoes | Plant outdoors (spring) | Mar 5 – May 5 |
| Onions | Start seeds indoors (spring) | Jan 22 – Feb 18 |
| Onions | Transplant outdoors (spring) | Mar 22 – Apr 20 |
| Broccoli | Start seeds indoors (spring) | Feb 15 – Mar 21 |
| Broccoli | Transplant outdoors (spring) | Mar 22 – Apr 20 |
| Broccoli | Start seeds indoors (fall) | Jun 24 – Jul 4 |
| Broccoli | Transplant outdoors (fall) | Jul 24 – Aug 4 |
| Cabbage | Start seeds indoors (spring) | Feb 5 – Mar 5 |
| Cabbage | Transplant outdoors (spring) | Mar 5 – Apr 5 |
| Cabbage | Start seeds indoors (fall) | Jun 14 – Jul 14 |
| Cabbage | Transplant outdoors (fall) | Jul 14 – Aug 14 |
| Leaf lettuce | Sow outdoors (spring) | Mar 5 – May 21 |
| Leaf lettuce | Sow outdoors (fall) | Jul 14 – Aug 30 |
| Spinach | Sow outdoors (spring) | Feb 26 – Apr 11 |
| Spinach | Sow outdoors (fall) | Jul 31 – Sep 4 |
| Radishes | Sow outdoors (spring) | Mar 5 – Apr 25 |
| Radishes | Sow outdoors (fall) | Jul 14 – Sep 14 |
| Kale | Sow outdoors (spring) | Mar 22 – Apr 11 |
| Kale | Sow outdoors (fall) | Jul 7 – Aug 14 |
| Carrots | Sow outdoors (spring) | Apr 5 – May 21 |
| Carrots | Sow outdoors (fall) | Jun 14 – Jul 30 |
| Garlic | Plant outdoors (fall) | Oct 14 – Nov 14 |
Where these dates come from
ZIP code 98811 is matched to the NOAA station Entiat Fish Hatchery, WA, 5.5 km away, at 1,027 ft elevation (243 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Entiat Fish Hatchery, WA (used) | 1,027 ft | Apr 5 | Oct 24 |
| Plain, WA | 1,936 ft | May 22 | Sep 22 |
| Waterville, WA | 2,664 ft | May 14 | Oct 1 |
| Chelan, WA | 1,194 ft | Apr 17 | Oct 22 |
Frost dates near Ardenvoir
- Entiat, WA 98822 · last May 14, first Oct 1
- Orondo, WA 98843 · last May 22, first Sep 22
- Manson, WA 98831 · last Apr 17, first Oct 22
- Leavenworth, WA 98826 · last May 22, first Sep 22
- Dryden, WA 98821 · last May 10, first Sep 30
- Cashmere, WA 98815 · last May 10, first Sep 30
- Peshastin, WA 98847 · last May 10, first Sep 30
- Monitor, WA 98836 · last Apr 4, first Oct 28
Frequently asked questions
- When is the last frost in Ardenvoir, WA?
- For ZIP code 98811, the average last spring frost (32°F) is April 5, based on NOAA 1991-2020 climate normals for the Entiat Fish Hatchery, WA weather station. There is a 1-in-10 chance of a frost after May 2.
- When is the first frost in Ardenvoir, WA?
- The average first fall frost (32°F) is October 24. There is a 1-in-10 chance of frost by September 29, so tender plants are at risk from that point on.
- How long is the growing season in 98811?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 200 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.