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 36603
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 36603 in zone 9a (the coldest night of a typical year: 20 to 25°F).
The nearest station, Mobile Downtown Airport, AL, is 4 miles from the ZIP's center: its last spring frost comes after February 21 in half of years and after March 15 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 |
|---|---|---|---|---|---|---|
| Mobile Downtown Airport, AL | 4 mi | 26 ft | February 21 | March 15 | December 6 | 9a |
| Mobile, ALMobile Regional Airport | 11 mi | 208 ft | March 3 | March 21 | November 25 | 9a |
| Fairhope (2 mi NE), AL | 14 mi | 23 ft | March 10 | March 30 | November 17 | – |
| Fairhope, AL3 mi NE | 14 mi | 95 ft | March 15 | April 2 | November 19 | – |
| Bay Minette, AL | 21 mi | 271 ft | February 28 | March 21 | November 25 | 8b |
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 Mobile Downtown Airport
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) | March 25 | March 14 | March 6 | February 12 | November 22 | November 5 |
| 32°F | March 15 | March 3 | February 21 | January 25 | December 6 | November 15 |
| 28°F (hard freeze) | March 6 | February 15 | February 2 | January 2 | December 30 | November 30 |
| 24°F | February 23 | February 1 | January 22 | December 27 | January 9 | December 14 |
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.