U.S. Frost Dates by Weather Station

NOAA station USW00013964 · Arkansas

Frost Dates for Fort Smith, AR

NOAA weather station Fort Smith Regional Airport (USW00013964), Arkansas · elevation 449 ft (137 m) · hardiness zone 8a*

  • Lower-risk planting dateafter April 11only 1 spring in 10 still has a frost later
  • Typical last frostMarch 2550% chance of a frost after it
  • Typical first fall frostNovember 650% chance of a frost before it
  • Frost-free season224 daystypical year, 32°F
  • Hardiness zone8acalculated*

The year at a glance

Frost season at Fort Smith, ARSpring: a frost after March 4 in 9 years out of 10, after March 25 in half of the years, after April 11 in 1 year out of 10. Fall: the first frost comes before October 23 in 1 year out of 10, before November 6 in half of the years, before November 21 in 9 years out of 10. Typical frost-free season: 224 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 25First frost ~Nov 6Frost season at Fort Smith, ARSpring: a frost after March 4 in 9 years out of 10, after March 25 in half of the years, after April 11 in 1 year out of 10. Fall: the first frost comes before October 23 in 1 year out of 10, before November 6 in half of the years, before November 21 in 9 years out of 10. Typical frost-free season: 224 days.JFMAMJJASONDLast frost ~Mar 25First frost ~Nov 6
frost likely chance fading 90% → 10% frost-free in a typical yearThe year at a glance. Blue: frost is likely; the gradient fades as the chance drops from 90% to 10%; green: the frost-free part of a typical year.

Frost dates (32°F)

Probability of frost, based on 27 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 11October 23
50% (typical)March 25November 6
90% (likely)March 4November 21
Frost-free season (32°F, 50% chance)
224 days
Hard frost (28°F), last in spring, 50% chance after
March 11
Hard frost (28°F), first in fall, 50% chance before
November 17

The last 15 years (2006–2020 normals)

Typical last frost March 21 (4 days earlier than the 30-year normal), typical first fall frost November 8 (2 days later). Frost-free season 234 days.

A shorter, more recent NOAA period. The 30-year normals above remain the main reference: 15 years carry more year-to-year noise.

Add these dates to your calendar Yearly reminders for the typical last frost, the lower-risk planting date and the typical first fall frost (.ics).

How the chance of frost changes with the date

Spring at Fort Smith: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 11, 20% April 6, 30% April 3, 40% March 30, 50% March 25, 60% March 21, 70% March 16, 80% March 12, 90% March 4. Observed last spring frost in recent years: 2021 April 21, 2022 April 1, 2023 March 20, 2024 March 27, 2025 March 6, 2026 March 17.Spring: last frostChance of a frost after this date10%50%90%Mar 1Apr 1Apr 11Mar 25Mar 42021: April 212022: April 12023: March 202024: March 272025: March 62026: March 17Fall at Fort Smith: chance of a frost before this dateFall, chance of a frost before the date: 10% October 23, 20% October 29, 30% November 1, 40% November 4, 50% November 6, 60% November 8, 70% November 13, 80% November 16, 90% November 21. Observed first fall frost in recent years: 2021 November 13, 2022 October 19, 2023 October 31, 2024 November 26, 2025 November 10.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Oct 23Nov 6Nov 212021: November 132022: October 192023: October 312024: November 262025: November 10
Two charts, because spring and fall answer different questions: in spring, the chance that a frost still comes after a date; in fall, the chance that the first frost has already come before it. NOAA publishes these odds from 10% to 90%, so the lines stop there. ◆ marks the actual date in each recent year.

What actually happened in recent years

Observed dates of the last spring and first fall frost (32°F) at this station; ◆ marks them on the charts above
YearLast spring frostFirst fall frost
2021April 21November 13
2022April 1October 19
2023March 20October 31
2024March 27November 26
2025March 6November 10
2026March 17season not over yet

What these dates mean

Fort Smith enjoys 224 days between the 32 °F 50% dates, March 25 and November 6, and within that window gardeners can expect a balanced chance of frost – a 50% chance of a frost later than March 25 in spring and a 50% chance of a frost earlier than November 6 in fall. The cautious plan for tender crops uses the April 11 spring date, which carries only a 10% chance of a later frost, and the October 23 fall date, which holds a 10% chance of an earlier frost. The 50% hard-frost dates are March 11 and November 17, marking when a frost of 28 °F is equally likely to have occurred. A hard frost at 28 °F can damage plants that survive a light frost at 32 °F, making it a more critical threshold for growers.

How to read the probabilities

The dates are probabilities from 30 years of weather, not a forecast for this year.

  • Spring: "10% after April 11" means that in about one spring out of ten a frost still happens after that date. The 90% date is the earliest: a frost after it happens in most years.
  • Fall: "10% before October 23" means that in about one fall out of ten the first frost arrives before that date.
  • 50% is the typical date: half of the years are earlier, half are later.
  • A light frost (32°F) damages tender plants; a hard frost (28°F) also stops most hardy vegetables.

Nearby weather stations

Map of weather stations near Fort Smith, ARNumbered nearest stations: 1 — Mountainburg, AR — 25 mi; 2 — Ozark, AR — 30 mi; 3 — Subiaco, AR — 41 mi; 4 — Blue Mountain Dam, AR — 43 mi; 5 — near Fayetteville, AR — 48 mi.AROK25 mi · 40 km1. Mountainburg, AR — 25 mi12. Ozark, AR — 30 mi23. Subiaco, AR — 41 mi34. Blue Mountain Dam, AR — 43 mi45. near Fayetteville, AR — 48 mi5
  1. Mountainburg, AR 25 mi (40 km)
  2. Ozark, AR 30 mi (49 km)
  3. Subiaco, AR 41 mi (66 km)
  4. Blue Mountain Dam, AR 43 mi (69 km)
  5. near Fayetteville, AR 48 mi (77 km)

Sources

* Hardiness zone 8a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 35.3331, -94.3625.