ZIP 98505 Zone 8b

Washington · USDA zone 8b, average annual extreme minimum 15°F to 20°F.

Nearest qualified station: OLYMPIA AP, WA US (USW00024227), 7.7 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is April 29. Median first 32°F is October 14. The 50% growing-season length is 169 days. The green band runs from the median last frost to the median first frost. Thin ticks mark the 10%, 50%, and 90% dates.

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.

ProbabilityDateHow to read it
90%April 11Earlier date. A last 32°F on or after this day is common.
50%April 29Median.
10%May 15Later 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.

ProbabilityDateHow to read it
10%September 28Earlier date. A first 32°F on or before this day is uncommon.
50%October 14Median.
90%November 1Later 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 longDays
10%195
50%169
90%144

28°F threshold

10%50%90%
Last, on or afterApril 29April 5March 12
First, on or beforeOctober 9November 1November 24
Season at least239 days210 days181 days

36°F threshold

10%50%90%
Last, on or afterMay 31May 15April 30
First, on or beforeSeptember 12September 28October 14
Season at least158 days135 days113 days

Station OLYMPIA AP, WA US (USW00024227). Completeness flag S, 30 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 57.3 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · Washington cities