Frost dates for 98033Kirkland, WA
The average last spring frost in Kirkland is March 8 and the average first fall frost is November 23, giving a typical growing season of about 259 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Mar 8
- Average first fall frost
- Nov 23
- Growing season
- 259 days
Safer after Mar 29 (1-in-10 risk)
Possible by Nov 4 (1-in-10 risk)
First frost typically in 21 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) | Mar 17 · Apr 4 · Apr 26 | Oct 24 · Nov 5 · Nov 22 | 215 days | 100% |
| Frost / freeze (32°F) | Feb 13 · Mar 8 · Mar 29 | Nov 4 · Nov 23 · Dec 16 | 259 days | 100% |
| Hard freeze (28°F) | Dec 27 · Feb 11 · Mar 1 | Nov 17 · Dec 11 · Jan 17 | 308 days | 96% |
Planting calendar for Kirkland
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 | Feb 5 – Apr 13 |
| Tomatoes | Transplant outdoors | Mar 24 – Aug 3 |
| Peppers | Start seeds indoors | Feb 5 – Mar 8 |
| Peppers | Transplant outdoors | Apr 7 – May 8 |
| Eggplant | Start seeds indoors | Feb 22 – Mar 23 |
| Eggplant | Transplant outdoors | Apr 7 – May 8 |
| Cucumbers | Sow outdoors | Apr 7 – Aug 13 |
| Summer squash | Sow outdoors | Mar 24 – May 8 |
| Winter squash & pumpkins | Sow outdoors | Apr 7 – May 8 |
| Snap beans | Sow outdoors | Mar 24 – Sep 5 |
| Sweet corn | Sow outdoors | Mar 24 – Aug 3 |
| Watermelon & cantaloupe | Sow outdoors | Apr 7 – May 8 |
| Okra | Sow outdoors | Mar 31 – Apr 23 |
| Peas | Sow outdoors (spring) | Feb 5 – Mar 23 |
| Potatoes | Plant outdoors (spring) | Feb 5 – Apr 7 |
| Onions | Start seeds indoors (spring) | Dec 25 – Jan 21 |
| Onions | Transplant outdoors (spring) | Feb 22 – Mar 23 |
| Broccoli | Start seeds indoors (spring) | Jan 18 – Feb 21 |
| Broccoli | Transplant outdoors (spring) | Feb 22 – Mar 23 |
| Broccoli | Start seeds indoors (fall) | Jul 24 – Aug 3 |
| Broccoli | Transplant outdoors (fall) | Aug 23 – Sep 3 |
| Cabbage | Start seeds indoors (spring) | Jan 8 – Feb 5 |
| Cabbage | Transplant outdoors (spring) | Feb 5 – Mar 8 |
| Cabbage | Start seeds indoors (fall) | Jul 14 – Aug 13 |
| Cabbage | Transplant outdoors (fall) | Aug 13 – Sep 13 |
| Leaf lettuce | Sow outdoors (spring) | Feb 5 – Apr 23 |
| Leaf lettuce | Sow outdoors (fall) | Aug 13 – Sep 29 |
| Spinach | Sow outdoors (spring) | Jan 29 – Mar 14 |
| Spinach | Sow outdoors (fall) | Aug 30 – Oct 4 |
| Radishes | Sow outdoors (spring) | Feb 5 – Mar 28 |
| Radishes | Sow outdoors (fall) | Aug 13 – Oct 14 |
| Kale | Sow outdoors (spring) | Feb 22 – Mar 14 |
| Kale | Sow outdoors (fall) | Aug 6 – Sep 13 |
| Carrots | Sow outdoors (spring) | Mar 8 – Apr 23 |
| Carrots | Sow outdoors (fall) | Jul 14 – Aug 29 |
| Garlic | Plant outdoors (fall) | Nov 13 – Dec 14 |
Where these dates come from
ZIP code 98033 is matched to the NOAA station Seattle Sand Pt Wsfo, WA, 5 km away, at 60 ft elevation (130 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Seattle Sand Pt Wsfo, WA (used) | 60 ft | Mar 8 | Nov 23 |
| Seattle Boeing Fld, WA | 20 ft | Mar 13 | Nov 17 |
| Renton Muni Ap, WA | 29 ft | Mar 13 | Nov 16 |
| Monroe, WA | 120 ft | Apr 17 | Oct 23 |
Frost dates near Kirkland
- Kirkland, WA 98083 · last Mar 8, first Nov 23
- Redmond, WA 98052 · last Mar 8, first Nov 23
- Medina, WA 98039 · last Mar 8, first Nov 23
- Bellevue, WA 98004 · last Mar 8, first Nov 23
- Seattle, WA 98115 · last Mar 8, first Nov 23
- Bothell, WA 98011 · last Mar 8, first Nov 23
- Kenmore, WA 98028 · last Mar 8, first Nov 23
- Woodinville, WA 98072 · last Mar 9, first Nov 17
Frequently asked questions
- When is the last frost in Kirkland, WA?
- For ZIP code 98033, the average last spring frost (32°F) is March 8, based on NOAA 1991-2020 climate normals for the Seattle Sand Pt Wsfo, WA weather station. There is a 1-in-10 chance of a frost after March 29.
- When is the first frost in Kirkland, WA?
- The average first fall frost (32°F) is November 23. There is a 1-in-10 chance of frost by November 4, so tender plants are at risk from that point on.
- How long is the growing season in 98033?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 259 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.