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 74145
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 74145 in zone 7b (the coldest night of a typical year: 5 to 10°F).
The nearest station, Tulsa R.L. Jones Jr. Airport, OK, is 7 miles from the ZIP's center: its last spring frost comes after March 30 in half of years and after April 17 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 R.L. Jones Jr. Airport, OK | 7 mi | 638 ft | March 30 | April 17 | November 4 | 7b |
| Tulsa, OKTulsa International Airport | 7 mi | 650 ft | March 31 | April 15 | November 4 | 7b |
| Bixby, OK | 8 mi | 605 ft | April 1 | April 20 | November 1 | – |
| Claremore, OK2 mi ENE | 23 mi | 588 ft | April 7 | April 24 | October 30 | 7a |
| Wagoner, OK | 30 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 R.L. Jones Jr. Airport
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 26 | April 17 | April 9 | March 26 | October 26 | October 12 |
| 32°F | April 17 | April 5 | March 30 | March 10 | November 4 | October 21 |
| 28°F (hard freeze) | April 3 | March 23 | March 15 | February 27 | November 14 | October 31 |
| 24°F | March 20 | March 10 | March 4 | February 12 | November 26 | November 7 |
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.