ZIP 97030 Zone 9a
Oregon · USDA zone 9a, average annual extreme minimum 20°F to 25°F.
Nearest qualified station: PORTLAND TROUTDALE AP, OR US (USW00024242), 3.1 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 18 | Earlier date. A last 32°F on or after this day is common. |
| 50% | March 16 | Median. |
| 10% | April 12 | 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% | October 30 | Earlier date. A first 32°F on or before this day is uncommon. |
| 50% | November 20 | Median. |
| 90% | December 17 | 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% | 288 |
| 50% | 250 |
| 90% | 216 |
28°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | March 10 | February 14 | December 27 |
| First, on or before | November 15 | December 15 | February 3 |
| Season at least | 358 days | 311 days | 268 days |
36°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | May 4 | April 19 | March 27 |
| First, on or before | October 11 | October 30 | November 22 |
| Season at least | 226 days | 198 days | 171 days |
Station PORTLAND TROUTDALE AP, OR US (USW00024242). Completeness flag R, 20 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 8.8 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.