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 84103
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 84103 in zone 6b (the coldest night of a typical year: -5 to 0°F).
The nearest station, City Creek Water Treatment Plant, UT, is 1 miles from the ZIP's center: its last spring frost comes after May 13 in half of years and after May 31 in one year in ten. By the USDA's method its plant hardiness zone is 6b.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| City Creek Water Treatment Plant, UT | 1 mi | 5,340 ft | May 13 | May 31 | October 7 | 6b |
| Salt Lake Triad Center, UT | 3 mi | 4,280 ft | March 31 | April 19 | November 8 | – |
| North Salt Lake, UTBountiful-Val Verda | 4 mi | 4,540 ft | April 24 | May 14 | October 19 | 7b |
| Salt Lake City E Bench, UT | 5 mi | 4,850 ft | April 25 | May 10 | October 18 | – |
| Bountiful, UTBountiful Bench | 6 mi | 4,950 ft | April 25 | May 14 | October 24 | 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 City Creek Water Treatment Plant
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 13 | June 4 | May 31 | May 13 | September 27 | September 13 |
| 32°F | May 31 | May 20 | May 13 | April 27 | October 7 | September 26 |
| 28°F (hard freeze) | May 15 | May 4 | April 28 | April 10 | October 19 | October 4 |
| 24°F | April 30 | April 15 | April 7 | March 20 | October 30 | October 15 |
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.