Frost dates for 98288Skykomish, WA
The average last spring frost in Skykomish is May 14 and the average first fall frost is October 17, giving a typical growing season of about 154 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 14
- Average first fall frost
- Oct 17
- Growing season
- 154 days
Safer after Jun 5 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 201 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 20 · Jun 10 · Jun 30 | Sep 14 · Oct 2 · Oct 15 | 114 days | 100% |
| Frost / freeze (32°F) | Apr 26 · May 14 · Jun 5 | Oct 1 · Oct 17 · Nov 1 | 154 days | 100% |
| Hard freeze (28°F) | Mar 31 · Apr 21 · May 12 | Oct 18 · Nov 2 · Nov 18 | 192 days | 100% |
Planting calendar for Skykomish
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 13 – Jun 19 |
| Tomatoes | Transplant outdoors | May 30 – Jun 27 |
| Peppers | Start seeds indoors | Apr 13 – May 14 |
| Peppers | Transplant outdoors | Jun 13 – Jul 14 |
| Eggplant | Start seeds indoors | Apr 30 – May 29 |
| Eggplant | Transplant outdoors | Jun 13 – Jul 14 |
| Cucumbers | Sow outdoors | Jun 13 – Jul 7 |
| Summer squash | Sow outdoors | May 30 – Jul 14 |
| Winter squash & pumpkins | Sow outdoors | Jun 13 – Jul 14 |
| Snap beans | Sow outdoors | May 30 – Jul 30 |
| Sweet corn | Sow outdoors | May 30 – Jun 27 |
| Watermelon & cantaloupe | Sow outdoors | Jun 13 – Jul 14 |
| Okra | Sow outdoors | Jun 6 – Jun 29 |
| Peas | Sow outdoors (spring) | Apr 13 – May 29 |
| Potatoes | Plant outdoors (spring) | Apr 13 – Jun 13 |
| Onions | Start seeds indoors (spring) | Mar 2 – Mar 29 |
| Onions | Transplant outdoors (spring) | Apr 30 – May 29 |
| Broccoli | Start seeds indoors (spring) | Mar 26 – Apr 29 |
| Broccoli | Transplant outdoors (spring) | Apr 30 – May 29 |
| Broccoli | Start seeds indoors (fall) | Jun 17 – Jun 27 |
| Broccoli | Transplant outdoors (fall) | Jul 17 – Jul 28 |
| Cabbage | Start seeds indoors (spring) | Mar 16 – Apr 13 |
| Cabbage | Transplant outdoors (spring) | Apr 13 – May 14 |
| Cabbage | Start seeds indoors (fall) | Jun 7 – Jul 7 |
| Cabbage | Transplant outdoors (fall) | Jul 7 – Aug 7 |
| Leaf lettuce | Sow outdoors (spring) | Apr 13 – Jun 29 |
| Leaf lettuce | Sow outdoors (fall) | Jul 7 – Aug 23 |
| Spinach | Sow outdoors (spring) | Apr 6 – May 20 |
| Spinach | Sow outdoors (fall) | Jul 24 – Aug 28 |
| Radishes | Sow outdoors (spring) | Apr 13 – Jun 3 |
| Radishes | Sow outdoors (fall) | Jul 7 – Sep 7 |
| Kale | Sow outdoors (spring) | Apr 30 – May 20 |
| Kale | Sow outdoors (fall) | Jun 30 – Aug 7 |
| Carrots | Sow outdoors (spring) | May 14 – Jun 29 |
| Carrots | Sow outdoors (fall) | Jun 7 – Jul 23 |
| Garlic | Plant outdoors (fall) | Oct 7 – Nov 7 |
Where these dates come from
ZIP code 98288 is matched to the NOAA station Stampede Pass, WA, 46.3 km away, at 3,959 ft elevation (868 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Stampede Pass, WA (used) | 3,959 ft | May 14 | Oct 17 |
| Baring, WA | 770 ft | Apr 14 | Oct 29 |
| Tolt S Fk Rsvr, WA | 2,000 ft | Apr 13 | Nov 10 |
| Startup 1 E, WA | 170 ft | Apr 15 | Oct 25 |
Frost dates near Skykomish
- Baring, WA 98224 · last Apr 14, first Oct 29
- Index, WA 98256 · last Apr 14, first Oct 29
- Gold Bar, WA 98251 · last Apr 15, first Oct 25
- Snoqualmie Pass, WA 98068 · last May 14, first Oct 17
- Sultan, WA 98294 · last Apr 15, first Oct 25
- Startup, WA 98293 · last Apr 15, first Oct 25
- North Bend, WA 98045 · last Mar 30, first Nov 7
- Snoqualmie, WA 98065 · last Mar 30, first Nov 7
Frequently asked questions
- When is the last frost in Skykomish, WA?
- For ZIP code 98288, the average last spring frost (32°F) is May 14, based on NOAA 1991-2020 climate normals for the Stampede Pass, WA weather station. There is a 1-in-10 chance of a frost after June 5.
- When is the first frost in Skykomish, WA?
- The average first fall frost (32°F) is October 17. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
- How long is the growing season in 98288?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 154 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.