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 74134
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 74134 in zone 7b (the coldest night of a typical year: 5 to 10°F).
The nearest station, Tulsa, OK, is 8 miles from the ZIP's center: its last spring frost comes after March 31 in half of years and after April 15 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 |
|---|---|---|---|---|---|---|
| Tulsa, OKTulsa International Airport | 8 mi | 650 ft | March 31 | April 15 | November 4 | 7b |
| Bixby, OK | 10 mi | 605 ft | April 1 | April 20 | November 1 | – |
| Tulsa R.L. Jones Jr. Airport, OK | 12 mi | 638 ft | March 30 | April 17 | November 4 | 7b |
| Claremore, OK2 mi ENE | 19 mi | 588 ft | April 7 | April 24 | October 30 | 7a |
| Wagoner, OK | 26 mi | 590 ft | March 29 | April 14 | November 5 | – |
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 Tulsa
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) | April 27 | April 18 | April 10 | March 26 | October 26 | October 11 |
| 32°F | April 15 | April 5 | March 31 | March 11 | November 4 | October 20 |
| 28°F (hard freeze) | April 5 | March 26 | March 17 | February 28 | November 13 | October 31 |
| 24°F | March 23 | March 12 | March 5 | February 17 | November 25 | 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.