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 27520
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 27520 in zone 8a (the coldest night of a typical year: 10 to 15°F).
The nearest station, Clayton, NC, is 2 miles from the ZIP's center: its last spring frost comes after April 7 in half of years and after April 20 in one year in ten. By the USDA's method its plant hardiness zone is 8a.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Clayton, NCClayton Water Treatment Plant | 2 mi | 300 ft | April 7 | April 20 | November 3 | 8a |
| Clayton (3 mi E), NC | 5 mi | 332 ft | March 28 | April 11 | November 8 | – |
| Smithfield, NC | 10 mi | 150 ft | March 29 | April 14 | November 5 | 8a |
| Garner, NC | 11 mi | 330 ft | April 1 | April 15 | November 1 | – |
| Raleigh (4 mi SW), NC | 14 mi | 420 ft | March 28 | April 12 | November 9 | 8a |
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 Clayton
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) | April 30 | April 23 | April 18 | April 3 | October 26 | October 14 |
| 32°F | April 20 | April 13 | April 7 | March 23 | November 3 | October 22 |
| 28°F (hard freeze) | April 12 | April 3 | March 27 | March 7 | November 14 | November 1 |
| 24°F | April 2 | March 20 | March 11 | February 23 | November 27 | November 10 |
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.