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 28227
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 28227 in zone 8a (the coldest night of a typical year: 10 to 15°F).
The nearest station, Monroe, NC, is 12 miles from the ZIP's center: its last spring frost comes after March 31 in half of years and after April 16 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 |
|---|---|---|---|---|---|---|
| Monroe, NCMonroe Airport | 12 mi | 679 ft | March 31 | April 16 | November 5 | 8a |
| Concord, NC | 16 mi | 700 ft | April 1 | April 16 | November 2 | 8a |
| Monroe (2 mi SE), NC | 16 mi | 550 ft | April 3 | April 18 | November 1 | – |
| Charlotte, NCCharlotte Douglas Airport | 18 mi | 728 ft | March 30 | April 14 | November 3 | 8a |
| Rock Hill, SCRock Hill York County Airport | 27 mi | 669 ft | March 31 | April 15 | November 4 | 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 Monroe
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 26 | April 18 | April 12 | March 26 | October 27 | October 14 |
| 32°F | April 16 | April 6 | March 31 | March 11 | November 5 | October 23 |
| 28°F (hard freeze) | April 5 | March 24 | March 16 | February 24 | November 16 | November 2 |
| 24°F | March 23 | March 11 | March 1 | February 3 | December 2 | November 12 |
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.