U.S. Frost Dates by Weather Station

NOAA station USC00291813 · New Mexico

Frost Dates for Cimarron, NM

NOAA weather station Cimarron 4 SW (USC00291813), New Mexico · elevation 6540 ft (1993 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 25only 1 spring in 10 still has a frost later
  • Typical last frostMay 1150% chance of a frost after it
  • Typical first fall frostOctober 350% chance of a frost before it
  • Frost-free season143 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Cimarron, NMSpring: a frost after April 30 in 9 years out of 10, after May 11 in half of the years, after May 25 in 1 year out of 10. Fall: the first frost comes before September 21 in 1 year out of 10, before October 3 in half of the years, before October 15 in 9 years out of 10. Typical frost-free season: 143 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 11First frost ~Oct 3Frost season at Cimarron, NMSpring: a frost after April 30 in 9 years out of 10, after May 11 in half of the years, after May 25 in 1 year out of 10. Fall: the first frost comes before September 21 in 1 year out of 10, before October 3 in half of the years, before October 15 in 9 years out of 10. Typical frost-free season: 143 days.JFMAMJJASONDLast frost ~May 11First frost ~Oct 3
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 28 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 25September 21
50% (typical)May 11October 3
90% (likely)April 30October 15
Frost-free season (32°F, 50% chance)
143 days
Hard frost (28°F), last in spring, 50% chance after
May 1
Hard frost (28°F), first in fall, 50% chance before
October 12

The last 15 years (2006–2020 normals)

Typical last frost May 13 (2 days later than the 30-year normal), typical first fall frost October 5 (2 days later). Frost-free season 144 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 Cimarron: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 25, 20% May 20, 30% May 16, 40% May 13, 50% May 11, 60% May 8, 70% May 6, 80% May 3, 90% April 30. Observed last spring frost in recent years: 2021 April 24, 2022 May 25, 2023 May 1, 2024 May 13.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 25May 11Apr 302021: April 242022: May 252023: May 12024: May 13Fall at Cimarron: chance of a frost before this dateFall, chance of a frost before the date: 10% September 21, 20% September 26, 30% September 29, 40% October 1, 50% October 3, 60% October 5, 70% October 8, 80% October 11, 90% October 15. Observed first fall frost in recent years: 2023 October 13.Fall: first frostChance of a frost before this date10%50%90%Oct 1Sep 21Oct 3Oct 152023: October 13
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 24incomplete record
2022May 25incomplete record
2023May 1October 13
2024May 13incomplete record
2025incomplete recordno data
2026no dataseason not over yet

What these dates mean

May 25 is the cautious spring date for light frost in Cimarron. With only a 10 % chance of a frost later than this day, a gardener can plan to set out tender crops after that date with minimal risk.

The 50% spring date is May 11 and the 50% fall date is October 3; each marks the point where a light frost is equally likely to have occurred or not. The 50% hard-frost dates are May 1 and October 12, showing an even chance of a 28 °F freeze. For a conservative schedule, the cautious dates are May 25 for planting and September 21 for finishing harvest, the latter carrying only a 10 % chance of a frost earlier. Hard frost, defined at 28 °F, is more damaging than a light frost at 32 °F because it can kill plant tissue that would survive a milder freeze.

How to read the probabilities

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

  • Spring: "10% after May 25" 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 September 21" 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 Cimarron, NMNumbered nearest stations: 1 — Eagle Nest, NM — 19 mi; 2 — Ocate, NM — 21 mi; 3 — Raton, NM — 42 mi; 4 — Gascon, NM — 49 mi; 5 — Las Vegas, NM — 57 mi.CO25 mi · 40 km1. Eagle Nest, NM — 19 mi12. Ocate, NM — 21 mi23. Raton, NM — 42 mi34. Gascon, NM — 49 mi45. Las Vegas, NM — 57 mi5
  1. Eagle Nest, NM 19 mi (30 km)
  2. Ocate, NM 21 mi (33 km)
  3. Raton, NM 42 mi (68 km)
  4. Gascon, NM 49 mi (78 km)
  5. Las Vegas, NM 57 mi (92 km)

Sources

* Hardiness zone 6a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 36.4661, -104.9456.