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 84124
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 84124 in zone 7b (the coldest night of a typical year: 5 to 10°F).
The nearest station, Cottonwood Heights, UT, is 4 miles from the ZIP's center: its last spring frost comes after April 29 in half of years and after May 30 in one year in ten. By the USDA's method its plant hardiness zone is 7a.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Cottonwood Heights, UTCottonwood Weir | 4 mi | 4,986 ft | April 29 | May 30 | October 22 | 7a |
| Salt Lake City E Bench, UT | 4 mi | 4,850 ft | April 25 | May 10 | October 18 | – |
| Mountain Dell Dam, UT | 6 mi | 5,420 ft | May 7 | May 27 | October 14 | 6b |
| Salt Lake Triad Center, UT | 8 mi | 4,280 ft | March 31 | April 19 | November 8 | – |
| City Creek Water Treatment Plant, UT | 10 mi | 5,340 ft | May 13 | May 31 | October 7 | 6b |
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 Cottonwood Heights
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) | June 9 | May 26 | May 13 | April 25 | October 11 | September 27 |
| 32°F | May 30 | May 8 | April 29 | April 10 | October 22 | October 6 |
| 28°F (hard freeze) | May 13 | April 21 | April 12 | March 21 | November 1 | October 17 |
| 24°F | April 19 | April 3 | March 26 | February 28 | November 12 | October 24 |
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.