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 28403
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 28403 in zone 8b (the coldest night of a typical year: 15 to 20°F).
The nearest station, Wilmington, NC, is 3 miles from the ZIP's center: its last spring frost comes after March 19 in half of years and after April 4 in one year in ten. By the USDA's method its plant hardiness zone is 8b.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Wilmington, NCWilmington Int'l Airport | 3 mi | 33 ft | March 19 | April 4 | November 20 | 8b |
| Myrtle Grove, NCWilmington (7 mi SE) | 5 mi | 30 ft | March 20 | April 8 | November 15 | – |
| Wilmington (7 mi N), NC | 7 mi | 40 ft | March 29 | April 11 | November 8 | – |
| Southport, NC5 mi N | 17 mi | 20 ft | March 24 | April 10 | November 17 | – |
| Moores Creek National Battlefield, NC | 21 mi | 22 ft | March 27 | April 12 | November 8 | – |
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 Wilmington
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 13 | April 4 | March 30 | March 14 | November 8 | October 27 |
| 32°F | April 4 | March 26 | March 19 | February 26 | November 20 | November 5 |
| 28°F (hard freeze) | March 23 | March 12 | March 2 | February 4 | December 3 | November 14 |
| 24°F | March 10 | February 24 | February 10 | January 12 | December 26 | November 30 |
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.