U.S. Frost Dates by Weather Station

NOAA station USC00148235 · Kansas

Frost Dates for Tribune, KS

NOAA weather station Tribune 1 W (USC00148235), Kansas · elevation 3634 ft (1108 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 16only 1 spring in 10 still has a frost later
  • Typical last frostMay 250% chance of a frost after it
  • Typical first fall frostOctober 1150% chance of a frost before it
  • Frost-free season160 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Tribune, KSSpring: a frost after April 20 in 9 years out of 10, after May 2 in half of the years, after May 16 in 1 year out of 10. Fall: the first frost comes before September 30 in 1 year out of 10, before October 11 in half of the years, before October 20 in 9 years out of 10. Typical frost-free season: 160 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 2First frost ~Oct 11Frost season at Tribune, KSSpring: a frost after April 20 in 9 years out of 10, after May 2 in half of the years, after May 16 in 1 year out of 10. Fall: the first frost comes before September 30 in 1 year out of 10, before October 11 in half of the years, before October 20 in 9 years out of 10. Typical frost-free season: 160 days.JFMAMJJASONDLast frost ~May 2First frost ~Oct 11
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 26 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 16September 30
50% (typical)May 2October 11
90% (likely)April 20October 20
Frost-free season (32°F, 50% chance)
160 days
Hard frost (28°F), last in spring, 50% chance after
April 23
Hard frost (28°F), first in fall, 50% chance before
October 19

The last 15 years (2006–2020 normals)

Typical last frost May 4 (2 days later than the 30-year normal), typical first fall frost October 14 (3 days later). Frost-free season 162 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 Tribune: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 16, 20% May 11, 30% May 8, 40% May 5, 50% May 2, 60% April 30, 70% April 29, 80% April 25, 90% April 20. Observed last spring frost in recent years: 2021 May 12, 2022 May 3, 2023 May 1, 2024 April 22, 2025 May 3, 2026 May 7.Spring: last frostChance of a frost after this date10%50%90%May 1May 16May 2Apr 202021: May 122022: May 32023: May 12024: April 222025: May 32026: May 7Fall at Tribune: chance of a frost before this dateFall, chance of a frost before the date: 10% September 30, 20% October 3, 30% October 5, 40% October 8, 50% October 11, 60% October 13, 70% October 15, 80% October 17, 90% October 20. Observed first fall frost in recent years: 2021 October 13, 2022 October 13, 2023 October 7, 2024 October 14.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 30Oct 11Oct 202021: October 132022: October 132023: October 72024: October 14
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 13
2022May 3October 13
2023May 1October 7
2024April 22October 14
2025May 3incomplete record
2026May 7season not over yet

What these dates mean

May 16 marks the cautious spring date for tender crops in Tribune, giving a gardener a 10% chance of a frost later and allowing the setting out of those crops. The 50% date of May 2 indicates an even-odds point for a frost, but it is not itself a frost date.

In the fall, September 30 is the cautious date with a 10% chance of a frost earlier, signaling when tender crops should be finished harvesting. The median 50% date of October 11 marks the point where a frost is equally likely, serving as a reference for planning.

A hard frost at 28 °F, which can occur on April 23 in spring and October 19 in fall, is more damaging to plants than 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 16" 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 Tribune, KSNumbered nearest stations: 1 — Sharon Springs, KS — 30 mi; 2 — Lakin, KS — 46 mi; 3 — Scott City, KS — 46 mi; 4 — Lamar, CO — 53 mi; 5 — Eads, CO — 54 mi.KSCO25 mi · 40 km1. Sharon Springs, KS — 30 mi12. Lakin, KS — 46 mi23. Scott City, KS — 46 mi34. Lamar, CO — 53 mi45. Eads, CO — 54 mi5
  1. Sharon Springs, KS 30 mi (48 km)
  2. Lakin, KS 46 mi (74 km)
  3. Scott City, KS 46 mi (74 km)
  4. Lamar, CO 53 mi (86 km)
  5. Eads, CO 54 mi (87 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: 38.4661, -101.7731.