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 45805
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 45805 in zone 6a (the coldest night of a typical year: -10 to -5°F).
The nearest station, Lima Wastewater Treatment Plant, OH, is 2 miles from the ZIP's center: its last spring frost comes after April 24 in half of years and after May 11 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 |
|---|---|---|---|---|---|---|
| Lima Wastewater Treatment Plant, OH | 2 mi | 850 ft | April 24 | May 11 | October 24 | 6b |
| Lima, OHLima Allen County Airport | 7 mi | 975 ft | April 22 | May 7 | October 22 | 6b |
| Pandora, OH | 18 mi | 770 ft | April 23 | May 9 | October 22 | 6a |
| Celina, OH3 mi NE | 22 mi | 866 ft | April 27 | May 10 | October 19 | 6a |
| Van Wert, OH1 mi S | 23 mi | 790 ft | April 21 | May 6 | October 26 | 6a |
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 Lima Wastewater 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) | May 20 | May 9 | May 3 | April 21 | October 13 | September 28 |
| 32°F | May 11 | April 30 | April 24 | April 12 | October 24 | October 10 |
| 28°F (hard freeze) | April 29 | April 20 | April 14 | March 31 | November 3 | October 22 |
| 24°F | April 16 | April 7 | April 1 | March 18 | November 15 | November 1 |
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.