Frost dates by ZIP code: The nearest NOAA stations to your ZIP, 1991-2020 normals
Enter a five-digit ZIP code. PlainClimate finds its center (Census Bureau 2024) and the five nearest NOAA stations with frost dates, and shows each station's last spring and first autumn 32°F dates with its distance and elevation.
Frost dates near ZIP 95139
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 95139 in zone 9b (the coldest night of a typical year: 25 to 30°F).
The nearest station, Mount Hamilton, CA, is 11 miles from the ZIP's center: its last spring frost comes after May 3 in half of years and after June 5 in one year in ten. By the USDA's method its plant hardiness zone is 9a.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Mount Hamilton, CA | 11 mi | 4,206 ft | May 3 | June 5 | November 18 | 9a |
| Los Gatos, CA | 11 mi | 365 ft | February 2 | March 14 | December 6 | – |
| San Jose station, CA | 12 mi | 67 ft | January 2 | January 23 | December 25 | – |
| San Jose, CA | 13 mi | 51 ft | January 12 | February 14 | December 22 | 10a |
| Gilroy, CA | 19 mi | 194 ft | February 24 | April 4 | November 27 | – |
Frost comes later in spring at higher and colder stations and earlier in low, open ground: prefer a station at a similar elevation to yours. Hardiness zone in the table: the USDA's rule (the average of each year's coldest night, 1991-2020) applied to the station's own record.
Every frost threshold at Mount Hamilton
NOAA publishes the dates for several temperatures and odds. A 30% spring date means a 3-in-10 chance of a later frost (the convention almanacs use); 50% is the median; 10% the cautious date.
| Threshold | Spring, 10% | Spring, 30% | Spring, 50% | Spring, 90% | Autumn, 50% | Autumn, 10% |
|---|---|---|---|---|---|---|
| 36°F (light frost) | June 18 | June 4 | May 27 | April 28 | October 29 | October 1 |
| 32°F | June 5 | May 16 | May 3 | April 7 | November 18 | October 22 |
| 28°F (hard freeze) | May 6 | April 22 | April 10 | February 23 | December 7 | November 10 |
| 24°F | April 11 | March 25 | March 1 | December 31 | January 1 | November 28 |
Source: NOAA NCEI 1991-2020 annual normals; ZIP centers: Census Bureau 2024 Gazetteer; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. Autumn 10%: one year in ten has its first frost before this date.