U.S. Frost Dates by Weather Station

NOAA station USC00035512 · Arkansas

Frost Dates for Ozark, AR

NOAA weather station Ozark 2 (USC00035512), Arkansas · elevation 830 ft (253 m) · hardiness zone 8a*

  • Lower-risk planting dateafter April 17only 1 spring in 10 still has a frost later
  • Typical last frostMarch 3050% chance of a frost after it
  • Typical first fall frostNovember 650% chance of a frost before it
  • Frost-free season222 daystypical year, 32°F
  • Hardiness zone8acalculated*

The year at a glance

Frost season at Ozark, ARSpring: a frost after March 10 in 9 years out of 10, after March 30 in half of the years, after April 17 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 23 in 9 years out of 10. Typical frost-free season: 222 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 30First frost ~Nov 6Frost season at Ozark, ARSpring: a frost after March 10 in 9 years out of 10, after March 30 in half of the years, after April 17 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 23 in 9 years out of 10. Typical frost-free season: 222 days.JFMAMJJASONDLast frost ~Mar 30First 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 17October 23
50% (typical)March 30November 6
90% (likely)March 10November 23
Frost-free season (32°F, 50% chance)
222 days
Hard frost (28°F), last in spring, 50% chance after
March 15
Hard frost (28°F), first in fall, 50% chance before
November 18

The last 15 years (2006–2020 normals)

Typical last frost March 31 (1 day later than the 30-year normal), typical first fall frost November 5 (1 day earlier). Frost-free season 224 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 Ozark: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 17, 20% April 10, 30% April 5, 40% April 2, 50% March 30, 60% March 25, 70% March 21, 80% March 17, 90% March 10. Observed last spring frost in recent years: 2021 April 22, 2022 April 10, 2023 March 21, 2024 March 28, 2025 February 25, 2026 March 17.Spring: last frostChance of a frost after this date10%50%90%Mar 1Apr 1May 1Apr 17Mar 30Mar 102021: April 222022: April 102023: March 212024: March 282025: February 252026: March 17Fall at Ozark: 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 3, 50% November 6, 60% November 9, 70% November 14, 80% November 18, 90% November 23. Observed first fall frost in recent years: 2021 November 13, 2022 October 19, 2023 October 31, 2024 November 26.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Oct 23Nov 6Nov 232021: November 132022: October 192023: October 312024: November 26
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 22November 13
2022April 10October 19
2023March 21October 31
2024March 28November 26
2025February 25incomplete record
2026March 17season not over yet

What these dates mean

April 17 is the cautious spring light-frost date in Ozark; with only a 10 % chance of a frost after that day, a gardener can plan to set out tender crops with relatively low risk.

The median light-frost dates are March 30 for spring and November 6 for fall; each represents a 50 % chance of a frost later (spring) or earlier (fall). The cautious fall date is October 23, when there is only a 10 % chance that a frost has arrived earlier, so harvesting tender crops can be timed around that point.

Hard frosts at 28 °F, recorded by the median dates March 15 and November 18, can damage plants more severely than the 32 °F light frosts, so they are an important separate risk to consider.

How to read the probabilities

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

  • Spring: "10% after April 17" 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 Ozark, ARNumbered nearest stations: 1 — Mountainburg, AR — 19 mi; 2 — Subiaco, AR — 19 mi; 3 — Blue Mountain Dam, AR — 30 mi; 4 — Fort Smith, AR — 30 mi; 5 — near Fayetteville, AR — 38 mi.AROK25 mi · 40 km1. Mountainburg, AR — 19 mi12. Subiaco, AR — 19 mi23. Blue Mountain Dam, AR — 30 mi34. Fort Smith, AR — 30 mi45. near Fayetteville, AR — 38 mi5
  1. Mountainburg, AR 19 mi (30 km)
  2. Subiaco, AR 19 mi (31 km)
  3. Blue Mountain Dam, AR 30 mi (48 km)
  4. Fort Smith, AR 30 mi (49 km)
  5. near Fayetteville, AR 38 mi (62 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: 35.5125, -93.8683.