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 42104
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 42104 in zone 7a (the coldest night of a typical year: 0 to 5°F).
The nearest station, Bowling Green, KY, is 6 miles from the ZIP's center: its last spring frost comes after April 5 in half of years and after April 21 in one year in ten. By the USDA's method its plant hardiness zone is 7b.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Bowling Green, KYBowling Green Warren County Airport | 6 mi | 528 ft | April 5 | April 21 | October 31 | 7b |
| Scottsville, KY | 15 mi | 743 ft | April 15 | May 2 | October 25 | 7a |
| Barren River Lake, KY | 18 mi | 615 ft | April 12 | April 30 | October 29 | 7a |
| Portland, TNPortland Sewage Plant | 20 mi | 794 ft | April 5 | April 19 | November 1 | 7b |
| Russellville, KY | 24 mi | 570 ft | April 9 | April 30 | October 28 | 7b |
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 Bowling Green
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 4 | April 24 | April 16 | April 2 | October 22 | October 9 |
| 32°F | April 21 | April 11 | April 5 | March 20 | October 31 | October 20 |
| 28°F (hard freeze) | April 7 | March 30 | March 24 | March 4 | November 10 | October 30 |
| 24°F | March 29 | March 18 | March 10 | February 20 | November 20 | November 6 |
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.