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 40023
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 40023 in zone 7a (the coldest night of a typical year: 0 to 5°F).
The nearest station, Shelbyville, KY, is 12 miles from the ZIP's center: its last spring frost comes after May 1 in half of years and after May 15 in one year in ten.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Shelbyville, KY1 mi E | 12 mi | 730 ft | May 1 | May 15 | October 10 | – |
| Louisville Weather Office, KY | 12 mi | 632 ft | April 6 | April 23 | November 1 | – |
| Taylorsville, KYTaylorsville Lake | 13 mi | 700 ft | April 23 | May 7 | October 16 | 7a |
| Louisville Bowman Field, KY | 14 mi | 540 ft | April 3 | April 19 | November 3 | 7b |
| Crestwood, KY4 mi NE | 14 mi | 780 ft | April 12 | May 1 | October 25 | – |
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 Shelbyville
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 25 | May 14 | May 9 | April 28 | October 1 | September 15 |
| 32°F | May 15 | May 6 | May 1 | April 19 | October 10 | September 24 |
| 28°F (hard freeze) | May 7 | April 29 | April 24 | April 10 | October 21 | October 4 |
| 24°F | April 30 | April 19 | April 13 | March 30 | November 1 | October 16 |
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.