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 99694
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 99694 in zone 4a (the coldest night of a typical year: -30 to -25°F).
The nearest station, Whites Crossing, AK, is 8 miles from the ZIP's center: its last spring frost comes after May 29 in half of years and after June 9 in one year in ten.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Whites Crossing, AK | 8 mi | 270 ft | May 29 | June 9 | September 7 | – |
| Willow, AKWillow West | 11 mi | 205 ft | May 15 | May 28 | September 18 | – |
| North Lakes, AKAnderson Lake | 16 mi | 458 ft | May 16 | May 31 | September 23 | – |
| Matanuska Experiment Farm, AK | 19 mi | 172 ft | May 14 | May 26 | September 20 | 4b |
| Eklutna Water Treatment Plant, AK | 21 mi | 640 ft | May 18 | May 30 | September 20 | 5a |
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 Whites Crossing
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% |
|---|---|---|---|---|---|---|
| 32°F | June 9 | June 2 | May 29 | May 13 | September 7 | August 24 |
| 28°F (hard freeze) | May 27 | May 21 | May 14 | April 29 | September 19 | September 3 |
| 24°F | May 17 | May 7 | May 1 | April 18 | September 29 | September 13 |
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.