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 08638
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 08638 in zone 7a (the coldest night of a typical year: 0 to 5°F).
The nearest station, Trenton State College, NJ, is 2 miles from the ZIP's center: its last spring frost comes after April 17 in half of years and after May 6 in one year in ten.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Trenton State College, NJ | 2 mi | 100 ft | April 17 | May 6 | October 28 | – |
| Trenton, NJTrenton-Mercer Airport | 3 mi | 184 ft | April 10 | April 25 | November 1 | 7b |
| Hightstown, NJ2 mi W | 11 mi | 100 ft | April 25 | May 12 | October 16 | 7a |
| Lambertville, NJ | 12 mi | 68 ft | April 16 | April 30 | October 19 | – |
| Neshaminy Falls, PA | 12 mi | 40 ft | April 21 | May 7 | October 25 | 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 Trenton State College
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 17 | May 8 | May 1 | April 16 | October 15 | October 1 |
| 32°F | May 6 | April 25 | April 17 | April 2 | October 28 | October 11 |
| 28°F (hard freeze) | April 17 | April 7 | April 2 | March 18 | November 7 | October 25 |
| 24°F | April 5 | March 28 | March 21 | March 4 | November 20 | November 3 |
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.