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 68135
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 68135 in zone 6a (the coldest night of a typical year: -10 to -5°F).
The nearest station, Gretna, NE, is 3 miles from the ZIP's center: its last spring frost comes after April 21 in half of years and after May 4 in one year in ten. By the USDA's method its plant hardiness zone is 6a.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Gretna, NE4 mi NE | 3 mi | 1,240 ft | April 21 | May 4 | October 18 | 6a |
| Valley, NEValley NWS | 12 mi | 1,145 ft | April 15 | April 29 | October 21 | 5b |
| Omaha #1, NE | 13 mi | 1,280 ft | April 16 | May 6 | October 18 | – |
| Springfield, NE7 mi E | 14 mi | 1,065 ft | April 17 | May 1 | October 19 | – |
| Ashland, NEAshland #2 | 15 mi | 1,118 ft | April 23 | May 5 | October 16 | 5b |
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 Gretna
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 14 | May 6 | May 1 | April 16 | October 8 | September 26 |
| 32°F | May 4 | April 27 | April 21 | April 5 | October 18 | October 4 |
| 28°F (hard freeze) | April 25 | April 17 | April 10 | March 27 | October 27 | October 14 |
| 24°F | April 19 | April 7 | April 1 | March 14 | November 4 | October 22 |
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.