ZIP 98166 Zone 9a
Washington · USDA zone 9a, average annual extreme minimum 20°F to 25°F.
Nearest qualified station: SEATTLE TACOMA INTL AP, WA US (USW00024233), 1.9 miles from the Census ZCTA internal point for this ZIP.
Outside the median season Growing seasonTicks: 10%, 50%, and 90%
Last 32°F in spring
NCEI’s probability is the chance the last spring minimum of 32°F or lower occurs on or after the date.
| Probability | Date | How to read it |
|---|---|---|
| 90% | February 5 | Earlier date. A last 32°F on or after this day is common. |
| 50% | March 2 | Median. |
| 10% | March 23 | Later date. A last 32°F on or after this day is uncommon. |
First 32°F in fall
NCEI’s probability is the chance the first autumn minimum of 32°F or lower occurs on or before the date.
| Probability | Date | How to read it |
|---|---|---|
| 10% | November 6 | Earlier date. A first 32°F on or before this day is uncommon. |
| 50% | November 23 | Median. |
| 90% | December 15 | Later date. A first 32°F on or before this day is common. |
32°F growing-season length
Days between the last spring 32°F and the first autumn 32°F. The figure is a length the season meets or exceeds at that probability, from NCEI, not a subtraction done on this site.
| Probability the season is at least this long | Days |
|---|---|
| 10% | 298 |
| 50% | 266 |
| 90% | 239 |
28°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | February 28 | February 4 | December 20 |
| First, on or before | November 17 | December 10 | January 16 |
| Season at least | 352 days | 315 days | 277 days |
36°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | April 21 | March 31 | March 13 |
| First, on or before | October 24 | November 7 | November 23 |
| Season at least | 244 days | 219 days | 195 days |
Station SEATTLE TACOMA INTL AP, WA US (USW00024233). Completeness flag S, 26 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 100%. Freeze dates are conditional on that threshold occurring. Elevation 112.8 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.