Frost dates for 98296Snohomish, WA
The average last spring frost in Snohomish is April 17 and the average first fall frost is October 23, giving a typical growing season of about 188 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 17
- Average first fall frost
- Oct 23
- Growing season
- 188 days
Safer after May 7 (1-in-10 risk)
Possible by Oct 7 (1-in-10 risk)
Last frost typically in 165 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 20 · May 5 · May 20 | Sep 21 · Oct 6 · Oct 25 | 153 days | 100% |
| Frost / freeze (32°F) | Mar 29 · Apr 17 · May 7 | Oct 7 · Oct 23 · Nov 9 | 188 days | 100% |
| Hard freeze (28°F) | Mar 6 · Mar 26 · Apr 14 | Oct 20 · Nov 8 · Nov 26 | 225 days | 100% |
Planting calendar for Snohomish
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 17 – May 23 |
| Tomatoes | Transplant outdoors | May 3 – Jul 3 |
| Peppers | Start seeds indoors | Mar 17 – Apr 17 |
| Peppers | Transplant outdoors | May 17 – Jun 17 |
| Eggplant | Start seeds indoors | Apr 3 – May 2 |
| Eggplant | Transplant outdoors | May 17 – Jun 17 |
| Cucumbers | Sow outdoors | May 17 – Jul 13 |
| Summer squash | Sow outdoors | May 3 – Jun 17 |
| Winter squash & pumpkins | Sow outdoors | May 17 – Jun 17 |
| Snap beans | Sow outdoors | May 3 – Aug 5 |
| Sweet corn | Sow outdoors | May 3 – Jul 3 |
| Watermelon & cantaloupe | Sow outdoors | May 17 – Jun 17 |
| Okra | Sow outdoors | May 10 – Jun 2 |
| Peas | Sow outdoors (spring) | Mar 17 – May 2 |
| Potatoes | Plant outdoors (spring) | Mar 17 – May 17 |
| Onions | Start seeds indoors (spring) | Feb 3 – Mar 2 |
| Onions | Transplant outdoors (spring) | Apr 3 – May 2 |
| Broccoli | Start seeds indoors (spring) | Feb 27 – Apr 2 |
| Broccoli | Transplant outdoors (spring) | Apr 3 – May 2 |
| Broccoli | Start seeds indoors (fall) | Jun 23 – Jul 3 |
| Broccoli | Transplant outdoors (fall) | Jul 23 – Aug 3 |
| Cabbage | Start seeds indoors (spring) | Feb 17 – Mar 17 |
| Cabbage | Transplant outdoors (spring) | Mar 17 – Apr 17 |
| Cabbage | Start seeds indoors (fall) | Jun 13 – Jul 13 |
| Cabbage | Transplant outdoors (fall) | Jul 13 – Aug 13 |
| Leaf lettuce | Sow outdoors (spring) | Mar 17 – Jun 2 |
| Leaf lettuce | Sow outdoors (fall) | Jul 13 – Aug 29 |
| Spinach | Sow outdoors (spring) | Mar 10 – Apr 23 |
| Spinach | Sow outdoors (fall) | Jul 30 – Sep 3 |
| Radishes | Sow outdoors (spring) | Mar 17 – May 7 |
| Radishes | Sow outdoors (fall) | Jul 13 – Sep 13 |
| Kale | Sow outdoors (spring) | Apr 3 – Apr 23 |
| Kale | Sow outdoors (fall) | Jul 6 – Aug 13 |
| Carrots | Sow outdoors (spring) | Apr 17 – Jun 2 |
| Carrots | Sow outdoors (fall) | Jun 13 – Jul 29 |
| Garlic | Plant outdoors (fall) | Oct 13 – Nov 13 |
Where these dates come from
ZIP code 98296 is matched to the NOAA station Monroe, WA, 7.4 km away, at 120 ft elevation (97 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Monroe, WA (used) | 120 ft | Apr 17 | Oct 23 |
| Everett Snohomish Ap, WA | 606 ft | Mar 9 | Nov 17 |
| Everett, WA | 60 ft | Mar 24 | Nov 2 |
| Seattle Sand Pt Wsfo, WA | 60 ft | Mar 8 | Nov 23 |
Frost dates near Snohomish
- Snohomish, WA 98290 · last Apr 17, first Oct 23
- Bothell, WA 98012 · last Mar 9, first Nov 17
- Mill Creek, WA 98082 · last Mar 9, first Nov 17
- Everett, WA 98208 · last Mar 9, first Nov 17
- Woodinville, WA 98072 · last Mar 9, first Nov 17
- Monroe, WA 98272 · last Apr 17, first Oct 23
- Lynnwood, WA 98087 · last Mar 9, first Nov 17
- Kenmore, WA 98028 · last Mar 8, first Nov 23
Frequently asked questions
- When is the last frost in Snohomish, WA?
- For ZIP code 98296, the average last spring frost (32°F) is April 17, based on NOAA 1991-2020 climate normals for the Monroe, WA weather station. There is a 1-in-10 chance of a frost after May 7.
- When is the first frost in Snohomish, WA?
- The average first fall frost (32°F) is October 23. 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 98296?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 188 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.