ZIP 95926 Zone 9b

California · USDA zone 9b, average annual extreme minimum 25°F to 30°F.

Nearest qualified station: CHICO UNIV FARM, CA US (USC00041715), 4 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is March 4. Median first 32°F is November 17. The 50% growing-season length is 257 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%February 8Earlier date. A last 32°F on or after this day is common.
50%March 4Median.
10%April 2Later 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%November 1Earlier date. A first 32°F on or before this day is uncommon.
50%November 17Median.
90%December 5Later 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%290
50%257
90%223

28°F threshold

10%50%90%
Last, on or afterMarch 1February 5January 1
First, on or beforeNovember 13December 3January 5
Season at least340 days307 days270 days

36°F threshold

10%50%90%
Last, on or afterApril 21April 5March 13
First, on or beforeOctober 21November 4November 19
Season at least239 days214 days190 days

Station CHICO UNIV FARM, CA US (USC00041715). Completeness flag R, 13 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 56.4 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · California cities