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Will it freeze in SeaTac in the next 7 nights?
No overnight lows at or below 32°F are forecast in SeaTac during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 45°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM PST to Fri, Nov 6, 6:00 AM PST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 45°F Above 36°F · Mostly Cloudy then Chance Light Rain
- Fri, Nov 6 50°F Above 36°F · Light Rain
- Sat, Nov 7 50°F Above 36°F · Light Rain
- Sun, Nov 8 42°F Above 36°F · Partly Cloudy
- Mon, Nov 9 48°F Above 36°F · Light Rain Likely
- Tue, Nov 10 51°F Above 36°F · Light Rain Likely
- Wed, Nov 11 49°F Above 36°F · Chance Light Rain
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in SeaTac
The median first fall hard-freeze date (28°F) is December 10, from NOAA’s 1991–2020 Climate Normals at Seattle Tacoma Intl Airport. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | Mar 13 · Mar 31 · Apr 21 | Oct 24 · Nov 7 · Nov 23 | 219 days |
| 32°F freeze | Feb 5 · Mar 2 · Mar 23 | Nov 6 · Nov 23 · Dec 15 | 266 days |
| 28°F hard freeze | Dec 20 · Feb 4 · Feb 28 | Nov 17 · Dec 10 · Jan 16 | 315 days |
Average high temperature by month
1991–2020 normals at Seattle Tacoma Intl Airport
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for SeaTac, WA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Seattle Tacoma Intl Airport (station USW00024233, elevation 370 ft), 0.7 mi from SeaTac. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near SeaTac
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Normandy Park, WA | 2.5 mi | Mar 2 | Nov 23 |
| Tukwila, WA | 2.5 mi | Mar 2 | Nov 23 |
| Burien, WA | 3.1 mi | Mar 2 | Nov 23 |
| Des Moines, WA | 3.7 mi | Mar 2 | Nov 23 |
| Kent, WA | 5.6 mi | Mar 20 | Nov 10 |
| Renton, WA | 5.6 mi | Mar 13 | Nov 16 |
| Newcastle, WA | 8.7 mi | Mar 13 | Nov 16 |
| Mercer Island, WA | 8.7 mi | Mar 13 | Nov 17 |
| Federal Way, WA | 9.3 mi | Mar 8 | Nov 14 |
| Auburn, WA | 11 mi | Mar 20 | Nov 10 |
Frequently asked questions
When is the last frost in SeaTac?
On average, the last spring frost (32°F) in SeaTac is around March 2. In about 1 year in 10 it comes after March 23, and in 9 years in 10 it comes after February 5.
When is the first frost in SeaTac?
The first fall frost (32°F) usually arrives around November 23. There’s a 10% chance of a freeze by November 6 and a 90% chance by December 15.
Can it frost in SeaTac after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after March 31.
What growing zone is SeaTac?
SeaTac is in USDA Plant Hardiness Zone 9a (average annual extreme minimum temperature 20 to 25°F), based on the 2023 USDA map for ZIP code 98158. See growing zones in Washington.
More: all Washington frost dates · Washington growing zones · UV index today in SeaTac · frost vs. freeze