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 23230
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 23230 in zone 7b (the coldest night of a typical year: 5 to 10°F).
The nearest station, Ashland, VA, is 9 miles from the ZIP's center: its last spring frost comes after April 10 in half of years and after April 29 in one year in ten. By the USDA's method its plant hardiness zone is 7b.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Ashland, VAAshland Hanover County Municipal Airport | 9 mi | 205 ft | April 10 | April 29 | October 31 | 7b |
| Richmond, VARichmond International Airport | 11 mi | 164 ft | April 3 | April 18 | November 4 | 7b |
| Ashland station, VA | 12 mi | 220 ft | April 10 | April 30 | October 29 | 7b |
| Sandston, VA | 12 mi | 165 ft | April 7 | April 21 | November 1 | 7b |
| Crozier, VA | 22 mi | 350 ft | April 17 | May 8 | October 27 | 7a |
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 Ashland
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) | May 10 | April 30 | April 23 | April 8 | October 21 | October 8 |
| 32°F | April 29 | April 16 | April 10 | March 27 | October 31 | October 17 |
| 28°F (hard freeze) | April 11 | April 2 | March 28 | March 12 | November 11 | October 29 |
| 24°F | March 31 | March 23 | March 16 | February 25 | November 25 | November 7 |
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.