Frost Dates for 74114 — Tulsa, Oklahoma

Half of springs at Tulsa International Airport, OK see their last 32°F night by March 31; only one in ten is past it by March 11, and one in ten still has one after April 15. Planting tender crops after April 5 leaves a 30% risk of a frost on them, after April 9 20%, and after April 15 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 86% of the 114 Oklahoma stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 4 in half of years, as early as October 20 one year in ten, and holds off past November 19 one year in ten. A hard freeze of 28°F follows 9 days later, around November 13; in spring the one-in-ten date for 28°F is April 5, 10 days before the 32°F one. The freeze-free season lasts 220 days in a typical year, longer than at 77% of the 114 Oklahoma stations; it reaches 243 days one year in ten and falls short of 198 one year in ten. On average 72 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 10 days longer, to about April 10, and return around October 26. Severe cold of 16°F or below comes in 98% of winters, usually between December 25 and February 12.

July is the warmest month at Tulsa International Airport, OK, averaging 94°F by day and 73°F at night; January is the coldest at 49°F and 28°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 45% of years.

Warmth for growing adds up to 5,332 growing degree days a year (base 50°F), more than at 77% of the 114 Oklahoma stations. 38% of them (2,036) have built up by the end of June, and July adds the most, 1,034. Precipitation totals 41.1 inches a year, most in May (5.7") and least in January (1.6"); May to September bring 52% of it.

The nearest other station, Tulsa R L Jones Jr Airport, OK, 6 miles south of Tulsa, has a last frost 1 day earlier (March 30), the same first-frost date.

The first measurable snow (0.1 inch or more) in Tulsa usually arrives around December 10, and the last of the season around February 27. Those are the middle dates across the winters of 1991–2020 at Tulsa International Airport, OK, 6 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 32 days after the last snow.

ZIP 74114 is 6 miles from Tulsa International Airport, OK, which stands at 650 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 21 other ZIP codes share the station; its figures are presented in full for 74055 (Owasso). The 2023 USDA Plant Hardiness Zone Map lists ZIP 74114 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.