ZIP 94401 Zone 10a

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

Nearest qualified station: SAN FRANCISCO INTL AP, CA US (USW00023234), 3.9 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is December 29. Median first 32°F is December 26. 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 11Earlier date. A last 32°F on or after this day is common.
50%December 29Median.
10%January 13Later 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 11Earlier date. A first 32°F on or before this day is uncommon.
50%December 26Median.
90%January 13Later 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%362

36°F threshold

10%50%90%
Last, on or afterFebruary 14January 8December 16
First, on or beforeDecember 5December 24January 24
Season at least365 days353 days319 days

Station SAN FRANCISCO INTL AP, CA US (USW00023234). 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 11.6%. Freeze dates are conditional on that threshold occurring. Elevation 2.4 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