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 66604
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 66604 in zone 6b (the coldest night of a typical year: -5 to 0°F).
The nearest station, Topeka - NWS, KS, is 6 miles from the ZIP's center: its last spring frost comes after April 16 in half of years and after April 27 in one year in ten.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Topeka - NWS, KS | 6 mi | 880 ft | April 16 | April 27 | October 22 | – |
| Topeka, KSTopeka Asos | 6 mi | 876 ft | April 12 | April 27 | October 23 | 6b |
| Topeka Forbes Field, KS | 7 mi | 1,067 ft | April 15 | April 30 | October 21 | 6a |
| Perry, KSPerry Lake | 18 mi | 957 ft | April 13 | April 30 | October 24 | 6a |
| Clinton Lake, KS | 22 mi | 980 ft | April 15 | May 1 | October 22 | – |
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 Topeka - NWS
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 5 | April 29 | April 24 | April 10 | October 13 | September 28 |
| 32°F | April 27 | April 20 | April 16 | April 1 | October 22 | October 6 |
| 28°F (hard freeze) | April 20 | April 12 | April 5 | March 17 | October 31 | October 17 |
| 24°F | April 10 | April 1 | March 24 | March 3 | November 10 | October 27 |
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.