U.S. Frost Dates by Weather Station

NOAA station USC00059295 · Colorado

Frost Dates for Yuma, CO

NOAA weather station Yuma (USC00059295), Colorado · elevation 4134 ft (1260 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 13only 1 spring in 10 still has a frost later
  • Typical last frostMay 150% chance of a frost after it
  • Typical first fall frostOctober 1250% chance of a frost before it
  • Frost-free season164 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Yuma, COSpring: a frost after April 16 in 9 years out of 10, after May 1 in half of the years, after May 13 in 1 year out of 10. Fall: the first frost comes before September 30 in 1 year out of 10, before October 12 in half of the years, before October 23 in 9 years out of 10. Typical frost-free season: 164 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 1First frost ~Oct 12Frost season at Yuma, COSpring: a frost after April 16 in 9 years out of 10, after May 1 in half of the years, after May 13 in 1 year out of 10. Fall: the first frost comes before September 30 in 1 year out of 10, before October 12 in half of the years, before October 23 in 9 years out of 10. Typical frost-free season: 164 days.JFMAMJJASONDLast frost ~May 1First frost ~Oct 12
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 29 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 13September 30
50% (typical)May 1October 12
90% (likely)April 16October 23
Frost-free season (32°F, 50% chance)
164 days
Hard frost (28°F), last in spring, 50% chance after
April 19
Hard frost (28°F), first in fall, 50% chance before
October 20

The last 15 years (2006–2020 normals)

Typical last frost May 1 (same as the 30-year normal), typical first fall frost October 16 (4 days later). Frost-free season 166 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 Yuma: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 13, 20% May 9, 30% May 6, 40% May 3, 50% May 1, 60% April 29, 70% April 26, 80% April 22, 90% April 16. Observed last spring frost in recent years: 2021 April 23, 2023 April 24.Spring: last frostChance of a frost after this date10%50%90%May 1May 13May 1Apr 162021: April 232023: April 24Fall at Yuma: chance of a frost before this dateFall, chance of a frost before the date: 10% September 30, 20% October 3, 30% October 6, 40% October 9, 50% October 12, 60% October 14, 70% October 17, 80% October 20, 90% October 23. Observed first fall frost in recent years: 2022 September 10.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 30Oct 12Oct 232022: September 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 23incomplete record
2022incomplete recordSeptember 10
2023April 24incomplete record
2024incomplete recordno data
2025no datano data
2026no dataseason not over yet

What these dates mean

September 30 is the cautious fall date to finish harvesting tender crops, carrying only a 10% chance that a light frost has arrived earlier. The median, October 12, marks a 50% chance of a light frost occurring before that day, while October 23 carries a 90% chance and would be a gamble for late tender crops. A hard frost at 28 °F is more damaging than a light frost at 32 °F because it can injure plant tissue that survives milder temperatures; the 50% hard-frost dates are April 19 in spring and October 20 in fall.

In spring, the 50% light-frost date is May 1, meaning there is an even chance of frost later than this day. Gardeners who prefer a low risk wait until May 13, the cautious date with only a 10% chance of frost after it, whereas planting on April 16 would involve a 90% chance of frost and is considered a gamble. The median hard-frost date of April 19 signals when a 28 °F event is as likely as not.

How to read the probabilities

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

  • Spring: "10% after May 13" 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 30" 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 Yuma, CONumbered nearest stations: 1 — near Akron, CO — 22 mi; 2 — Akron Washington County Airport, CO — 26 mi; 3 — Wray, CO — 27 mi; 4 — Leroy, CO — 31 mi; 5 — Joes, CO — 32 mi.NEKS25 mi · 40 km1. near Akron, CO — 22 mi12. Akron Washington County Airport, CO — 26 mi23. Wray, CO — 27 mi34. Leroy, CO — 31 mi45. Joes, CO — 32 mi5
  1. near Akron, CO 22 mi (36 km)
  2. Akron Washington County Airport, CO 26 mi (42 km)
  3. Wray, CO 27 mi (44 km)
  4. Leroy, CO 31 mi (49 km)
  5. Joes, CO 32 mi (52 km)

Sources

* Hardiness zone 5b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 40.1236, -102.7217.