U.S. Frost Dates by Weather Station

NOAA station USC00055484 · Colorado

Frost Dates for Meeker, CO

NOAA weather station Meeker (USC00055484), Colorado · elevation 6229 ft (1899 m) · hardiness zone 4b*

  • Lower-risk planting dateafter June 23only 1 spring in 10 still has a frost later
  • Typical last frostJune 450% chance of a frost after it
  • Typical first fall frostSeptember 1650% chance of a frost before it
  • Frost-free season104 daystypical year, 32°F
  • Hardiness zone4bcalculated*

The year at a glance

Frost season at Meeker, COSpring: a frost after May 21 in 9 years out of 10, after June 4 in half of the years, after June 23 in 1 year out of 10. Fall: the first frost comes before September 3 in 1 year out of 10, before September 16 in half of the years, before October 1 in 9 years out of 10. Typical frost-free season: 104 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Jun 4First frost ~Sep 16Frost season at Meeker, COSpring: a frost after May 21 in 9 years out of 10, after June 4 in half of the years, after June 23 in 1 year out of 10. Fall: the first frost comes before September 3 in 1 year out of 10, before September 16 in half of the years, before October 1 in 9 years out of 10. Typical frost-free season: 104 days.JFMAMJJASONDLast frost ~Jun 4First frost ~Sep 16
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)June 23September 3
50% (typical)June 4September 16
90% (likely)May 21October 1
Frost-free season (32°F, 50% chance)
104 days
Hard frost (28°F), last in spring, 50% chance after
May 21
Hard frost (28°F), first in fall, 50% chance before
September 27

The last 15 years (2006–2020 normals)

Typical last frost June 10 (6 days later than the 30-year normal), typical first fall frost September 10 (6 days earlier). Frost-free season 92 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 Meeker: chance of a frost after this dateSpring, chance of a frost after the date: 10% June 23, 20% June 16, 30% June 11, 40% June 7, 50% June 4, 60% June 1, 70% May 29, 80% May 25, 90% May 21. Observed last spring frost in recent years: 2021 June 12, 2022 June 15, 2023 June 23, 2024 May 31, 2026 June 30.Spring: last frostChance of a frost after this date10%50%90%Jun 1Jul 1Jun 23Jun 4May 212021: June 122022: June 152023: June 232024: May 312026: June 30Fall at Meeker: chance of a frost before this dateFall, chance of a frost before the date: 10% September 3, 20% September 7, 30% September 11, 40% September 14, 50% September 16, 60% September 19, 70% September 22, 80% September 26, 90% October 1. Observed first fall frost in recent years: 2021 September 18, 2022 September 10, 2023 September 7, 2024 August 31.Fall: first frostChance of a frost before this date10%50%90%Sep 1Oct 1Sep 3Sep 16Oct 12021: September 182022: September 102023: September 72024: August 31
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
2021June 12September 18
2022June 15September 10
2023June 23September 7
2024May 31August 31
2025incomplete recordno data
2026June 30season not over yet

What these dates mean

Setting out tender crops on the early spring date, May 21, is a gamble in Meeker because there is a 90 % chance of a frost later than that date. The cautious spring date for tender crops is June 23, when only a 10 % chance of a later frost remains.

In the fall the cautious date to finish harvesting tender crops is September 3, with a 10 % chance that a frost has already arrived, while October 1 carries a 90 % gamble of a frost already occurring. The 50 % dates—June 4 in spring and September 16 in fall—are the points at which a light frost is equally likely before or after, offering a midpoint reference for garden timing. The hard-frost 50 % dates are May 21 and September 27; a hard frost at 28 °F can damage or kill plants that survive a 32 °F light frost, making those dates especially critical. The interval between the two 32°F 50 % dates—June 4 and September 16—is 104 days, marking the length of the frost-free calendar window. The record covers 28 years, giving confidence in these probability estimates.

How to read the probabilities

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

  • Spring: "10% after June 23" 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 3" 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 Meeker, CONumbered nearest stations: 1 — Maybell, CO — 35 mi; 2 — Altenbern, CO — 45 mi; 3 — Rangely, CO — 46 mi; 4 — Hayden, CO — 47 mi; 5 — Palisade, CO — 68 mi.COUT25 mi · 40 km1. Maybell, CO — 35 mi12. Altenbern, CO — 45 mi23. Rangely, CO — 46 mi34. Hayden, CO — 47 mi45. Palisade, CO — 68 mi5
  1. Maybell, CO 35 mi (56 km)
  2. Altenbern, CO 45 mi (72 km)
  3. Rangely, CO 46 mi (74 km)
  4. Hayden, CO 47 mi (75 km)
  5. Palisade, CO 68 mi (109 km)

Sources

* Hardiness zone 4b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 40.0358, -107.9058.