ZIP 91104 Zone 10a

California · USDA zone 10a, average annual extreme minimum 30°F to 35°F.

Nearest qualified station: PASADENA, CA US (USC00046719), 1.7 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is January 8. Median first 32°F is January 7. The 50% growing-season length is 365 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%December 20Earlier date. A last 32°F on or after this day is common.
50%January 8Median.
10%February 17Later 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%December 20Earlier date. A first 32°F on or before this day is uncommon.
50%January 7Median.
90%February 14Later 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%365
50%365
90%363

36°F threshold

10%50%90%
Last, on or afterFebruary 27January 17December 18
First, on or beforeDecember 5December 28February 7
Season at least365 days344 days292 days

Station PASADENA, CA US (USC00046719). Completeness flag S, 25 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 12.9%. Freeze dates are conditional on that threshold occurring. Elevation 263.3 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