Frost Dates for 72901 — Fort Smith, Arkansas

Half of springs at Fort Smith Regional Airport, AR see their last 32°F night by March 25; only one in ten is past it by March 4, and one in ten still has one after April 11. Planting tender crops after April 3 leaves a 30% risk of a frost on them, after April 6 20%, and after April 11 10%. The 17 days between the even-odds date and the one-in-ten date is narrower than at 41% of the 105 Arkansas stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 6 in half of years, as early as October 23 one year in ten, and holds off past November 21 one year in ten. A hard freeze of 28°F follows 11 days later, around November 17; in spring the one-in-ten date for 28°F is April 2, 9 days before the 32°F one. The freeze-free season lasts 224 days in a typical year, shorter than at 47% of the 105 Arkansas stations; it reaches 248 days one year in ten and falls short of 202 one year in ten. On average 63 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 14 days longer, to about April 8, and return around October 28. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 83%.

July is the warmest month at Fort Smith Regional Airport, AR, averaging 94°F by day and 72°F at night; January is the coldest at 51°F and 30°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 35% of years.

Warmth for growing adds up to 5,500 growing degree days a year (base 50°F), more than at 77% of the 105 Arkansas stations. 39% of them (2,129) have built up by the end of June, and July adds the most, 1,026. Precipitation totals 47.4 inches a year, most in May (5.6") and least in February (2.7"); May to September bring 45% of it.

The nearest other station, Sallisaw 2 NW, OK, 23 miles west of Fort Smith and 211 feet higher, has a last frost 5 days later (March 30), a first frost 1 day later (November 7), a season 1 day shorter.

Measurable snow is rare here: only 5 of 18 winters from 1991 to 2020 recorded 0.1 inch or more at Spiro, OK, 14.9 miles away, so there is no typical first-snow date to plan around.

ZIP 72901 is 4 miles from Fort Smith Regional Airport, AR, which stands at 449 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 14 other ZIP codes share the station; its figures are presented in full for 72956 (Van Buren). The 2023 USDA Plant Hardiness Zone Map lists ZIP 72901 in zone 8a, the band where the coldest night of the year averaged 10 to 15°F (-12.2 to -9.4°C) over 1991–2020; a zone describes winter lows, not frost dates.