U.S. Frost Dates by Weather Station

NOAA station USC00054082 · Colorado

Frost Dates for Holyoke, CO

NOAA weather station Holyoke (USC00054082), Colorado · elevation 3780 ft (1152 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 23only 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 season144 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Holyoke, COSpring: a frost after April 30 in 9 years out of 10, after May 11 in half of the years, after May 23 in 1 year out of 10. Fall: the first frost comes before September 20 in 1 year out of 10, before October 3 in half of the years, before October 13 in 9 years out of 10. Typical frost-free season: 144 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 11First frost ~Oct 3Frost season at Holyoke, COSpring: a frost after April 30 in 9 years out of 10, after May 11 in half of the years, after May 23 in 1 year out of 10. Fall: the first frost comes before September 20 in 1 year out of 10, before October 3 in half of the years, before October 13 in 9 years out of 10. Typical frost-free season: 144 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 29 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 23September 20
50% (typical)May 11October 3
90% (likely)April 30October 13
Frost-free season (32°F, 50% chance)
144 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 11 (same as the 30-year normal), typical first fall frost October 6 (3 days later). Frost-free season 147 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 Holyoke: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 23, 20% May 18, 30% May 15, 40% May 13, 50% May 11, 60% May 9, 70% May 7, 80% May 4, 90% April 30. Observed last spring frost in recent years: 2021 May 12, 2022 May 22, 2023 May 2, 2024 May 4, 2025 May 3, 2026 May 2.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 23May 11Apr 302021: May 122022: May 222023: May 22024: May 42025: May 32026: May 2Fall at Holyoke: chance of a frost before this dateFall, chance of a frost before the date: 10% September 20, 20% September 26, 30% September 29, 40% October 1, 50% October 3, 60% October 5, 70% October 7, 80% October 10, 90% October 13. Observed first fall frost in recent years: 2021 October 14, 2022 October 8, 2023 October 7, 2024 October 1, 2025 October 19.Fall: first frostChance of a frost before this date10%50%90%Oct 1Sep 20Oct 3Oct 132021: October 142022: October 82023: October 72024: October 12025: October 19
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
2021May 12October 14
2022May 22October 8
2023May 2October 7
2024May 4October 1
2025May 3October 19
2026May 2season not over yet

What these dates mean

Planting tender crops on April 30 in Holyoke carries a 90 % chance that a light frost will occur later, making that early date a gamble for growers.

The 50 % light-frost dates are May 11 in spring and October 3 in fall; each marks the point where the odds of a frost are even. The 50 % hard-frost dates are May 1 and October 12, and a hard frost at 28 °F can damage plants more severely than a light frost at 32 °F.

For a cautious spring plan, gardeners use the May 23 date, which has only a 10 % chance of a later frost, while the cautious fall cut-off is September 20, with a 10 % chance that a frost has arrived earlier. The period between the two 32 °F 50 % dates spans 144 days, based on 29 years of record.

How to read the probabilities

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

  • Spring: "10% after May 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 20" 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 Holyoke, CONumbered nearest stations: 1 — Sedgwick, CO — 24 mi; 2 — Wray, CO — 33 mi; 3 — Leroy, CO — 34 mi; 4 — Yuma, CO — 35 mi; 5 — Lodgepole, NE — 44 mi.NEKSWY25 mi · 40 km1. Sedgwick, CO — 24 mi12. Wray, CO — 33 mi23. Leroy, CO — 34 mi34. Yuma, CO — 35 mi45. Lodgepole, NE — 44 mi5
  1. Sedgwick, CO 24 mi (39 km)
  2. Wray, CO 33 mi (53 km)
  3. Leroy, CO 34 mi (55 km)
  4. Yuma, CO 35 mi (57 km)
  5. Lodgepole, NE 44 mi (72 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: 40.5453, -102.3411.