U.S. Frost Dates by Weather Station

NOAA station USC00027390 · Arizona

Frost Dates for Safford, AZ

NOAA weather station Safford Agricultural Center (USC00027390), Arizona · elevation 2954 ft (900 m) · hardiness zone 8b*

  • Lower-risk planting dateafter April 14only 1 spring in 10 still has a frost later
  • Typical last frostMarch 2550% chance of a frost after it
  • Typical first fall frostNovember 950% chance of a frost before it
  • Frost-free season228 daystypical year, 32°F
  • Hardiness zone8bcalculated*

The year at a glance

Frost season at Safford, AZSpring: a frost after March 5 in 9 years out of 10, after March 25 in half of the years, after April 14 in 1 year out of 10. Fall: the first frost comes before October 23 in 1 year out of 10, before November 9 in half of the years, before November 25 in 9 years out of 10. Typical frost-free season: 228 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 25First frost ~Nov 9Frost season at Safford, AZSpring: a frost after March 5 in 9 years out of 10, after March 25 in half of the years, after April 14 in 1 year out of 10. Fall: the first frost comes before October 23 in 1 year out of 10, before November 9 in half of the years, before November 25 in 9 years out of 10. Typical frost-free season: 228 days.JFMAMJJASONDLast frost ~Mar 25First frost ~Nov 9
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 26 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 14October 23
50% (typical)March 25November 9
90% (likely)March 5November 25
Frost-free season (32°F, 50% chance)
228 days
Hard frost (28°F), last in spring, 50% chance after
March 3
Hard frost (28°F), first in fall, 50% chance before
November 22

The last 15 years (2006–2020 normals)

Typical last frost March 25 (same as the 30-year normal), typical first fall frost November 12 (3 days later). Frost-free season 229 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 Safford: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 14, 20% April 7, 30% April 3, 40% March 30, 50% March 25, 60% March 20, 70% March 15, 80% March 10, 90% March 5. Observed last spring frost in recent years: 2022 April 14, 2023 April 6, 2024 April 7, 2025 March 21, 2026 March 7.Spring: last frostChance of a frost after this date10%50%90%Mar 1Apr 1Apr 14Mar 25Mar 52022: April 142023: April 62024: April 72025: March 212026: March 7Fall at Safford: chance of a frost before this dateFall, chance of a frost before the date: 10% October 23, 20% October 30, 30% November 3, 40% November 6, 50% November 9, 60% November 13, 70% November 16, 80% November 20, 90% November 25. Observed first fall frost in recent years: 2022 October 25, 2023 November 24, 2024 October 31, 2025 December 2.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Oct 23Nov 9Nov 252022: October 252023: November 242024: October 312025: December 2
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
2021incomplete recordincomplete record
2022April 14October 25
2023April 6November 24
2024April 7October 31
2025March 21December 2
2026March 7season not over yet

What these dates mean

April 14 is the cautious spring date, giving a gardener a 10 % chance that a light frost will still occur later and allowing the setting out of tender crops with relatively low risk. The 50 % date is March 25, representing an even-odds point for a light frost in spring, while the early-spring date of March 5 carries a 90 % chance and should be treated as a gamble.

October 23 is the cautious fall date, marking a 10 % chance that a light frost has already arrived and offering a reliable time to finish harvesting tender crops. The 50 % date is November 9, an even-odds point for a light frost in autumn, and the late-fall date of November 25 carries a 90 % chance, making it a risky choice. Hard-frost median dates are March 3 in spring and November 22 in fall; hard frost at 28 °F can injure plants more severely than a light frost at 32 °F, so those dates are crucial for protecting vulnerable crops.

How to read the probabilities

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

  • Spring: "10% after April 14" 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 Safford, AZNumbered nearest stations: 1 — Duncan, AZ — 33 mi; 2 — San Simon, AZ — 45 mi; 3 — Cliff, NM — 68 mi; 4 — Benson, AZ — 72 mi; 5 — Tombstone, AZ — 80 mi.AZNM25 mi · 40 km1. Duncan, AZ — 33 mi12. San Simon, AZ — 45 mi23. Cliff, NM — 68 mi34. Benson, AZ — 72 mi45. Tombstone, AZ — 80 mi5
  1. Duncan, AZ 33 mi (53 km)
  2. San Simon, AZ 45 mi (72 km)
  3. Cliff, NM 68 mi (110 km)
  4. Benson, AZ 72 mi (116 km)
  5. Tombstone, AZ 80 mi (128 km)

Sources

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

Station coordinates: 32.815, -109.6808.