U.S. Frost Dates by Weather Station

NOAA station USW00093058 · Colorado

Frost Dates for Pueblo, CO

NOAA weather station Pueblo Memorial Airport (USW00093058), Colorado · elevation 4720 ft (1439 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 12only 1 spring in 10 still has a frost later
  • Typical last frostApril 3050% chance of a frost after it
  • Typical first fall frostOctober 950% chance of a frost before it
  • Frost-free season161 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Pueblo, COSpring: a frost after April 18 in 9 years out of 10, after April 30 in half of the years, after May 12 in 1 year out of 10. Fall: the first frost comes before September 27 in 1 year out of 10, before October 9 in half of the years, before October 21 in 9 years out of 10. Typical frost-free season: 161 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 30First frost ~Oct 9Frost season at Pueblo, COSpring: a frost after April 18 in 9 years out of 10, after April 30 in half of the years, after May 12 in 1 year out of 10. Fall: the first frost comes before September 27 in 1 year out of 10, before October 9 in half of the years, before October 21 in 9 years out of 10. Typical frost-free season: 161 days.JFMAMJJASONDLast frost ~Apr 30First frost ~Oct 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 29 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 12September 27
50% (typical)April 30October 9
90% (likely)April 18October 21
Frost-free season (32°F, 50% chance)
161 days
Hard frost (28°F), last in spring, 50% chance after
April 19
Hard frost (28°F), first in fall, 50% chance before
October 18

The last 15 years (2006–2020 normals)

Typical last frost April 29 (1 day earlier than the 30-year normal), typical first fall frost October 12 (3 days later). Frost-free season 163 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 Pueblo: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 12, 20% May 7, 30% May 4, 40% May 2, 50% April 30, 60% April 28, 70% April 26, 80% April 22, 90% April 18. Observed last spring frost in recent years: 2021 April 29, 2022 May 3, 2023 April 27, 2024 April 15, 2025 May 3, 2026 May 7.Spring: last frostChance of a frost after this date10%50%90%May 1May 12Apr 30Apr 182021: April 292022: May 32023: April 272024: April 152025: May 32026: May 7Fall at Pueblo: chance of a frost before this dateFall, chance of a frost before the date: 10% September 27, 20% October 1, 30% October 4, 40% October 7, 50% October 9, 60% October 11, 70% October 14, 80% October 17, 90% October 21. Observed first fall frost in recent years: 2021 October 15, 2022 October 18, 2023 October 14, 2024 October 25, 2025 October 19.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 27Oct 9Oct 212021: October 152022: October 182023: October 142024: October 252025: 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
2021April 29October 15
2022May 3October 18
2023April 27October 14
2024April 15October 25
2025May 3October 19
2026May 7season not over yet

What these dates mean

161 days separate the two 32°F 50% dates—April 30 and October 9—so that most of the growing season falls between a point where a light frost is as likely as not in spring and a comparable point in fall. For a gardener, the April 30 date marks a 50 % chance that a light frost could still occur later, while the October 9 date marks a 50 % chance that a light frost could already have arrived earlier.

The cautious spring plan uses the May 12 date, which carries only a 10 % chance of a light frost later, whereas planting on April 18 would be a gamble with a 90 % chance of frost later. In fall, the cautious finish date is September 27, with a 10 % chance of a light frost earlier; aiming for October 21 would be risky, having a 90 % chance of frost earlier. The median hard-frost dates are April 19 in spring and October 18 in fall, and a hard frost at 28 °F can damage plants that survive a light frost at 32 °F.

How to read the probabilities

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

  • Spring: "10% after May 12" 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 27" 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 Pueblo, CONumbered nearest stations: 1 — Tacony, CO — 24 mi; 2 — Colorado Springs, CO — 37 mi; 3 — Canon City, CO — 41 mi; 4 — Walsenburg, CO — 48 mi; 5 — Westcliffe, CO — 54 mi.CO25 mi · 40 km1. Tacony, CO — 24 mi12. Colorado Springs, CO — 37 mi23. Canon City, CO — 41 mi34. Walsenburg, CO — 48 mi45. Westcliffe, CO — 54 mi5
  1. Tacony, CO 24 mi (39 km)
  2. Colorado Springs, CO 37 mi (60 km)
  3. Canon City, CO 41 mi (66 km)
  4. Walsenburg, CO 48 mi (78 km)
  5. Westcliffe, CO 54 mi (86 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: 38.29, -104.4983.