U.S. Frost Dates by Weather Station

NOAA station USC00143984 · Kansas

Frost Dates for Iola, KS

NOAA weather station Iola 1 W (USC00143984), Kansas · elevation 954 ft (291 m) · hardiness zone 6b*

  • Lower-risk planting dateafter April 24only 1 spring in 10 still has a frost later
  • Typical last frostApril 850% chance of a frost after it
  • Typical first fall frostOctober 2650% chance of a frost before it
  • Frost-free season200 daystypical year, 32°F
  • Hardiness zone6bcalculated*

The year at a glance

Frost season at Iola, KSSpring: a frost after March 25 in 9 years out of 10, after April 8 in half of the years, after April 24 in 1 year out of 10. Fall: the first frost comes before October 13 in 1 year out of 10, before October 26 in half of the years, before November 7 in 9 years out of 10. Typical frost-free season: 200 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 8First frost ~Oct 26Frost season at Iola, KSSpring: a frost after March 25 in 9 years out of 10, after April 8 in half of the years, after April 24 in 1 year out of 10. Fall: the first frost comes before October 13 in 1 year out of 10, before October 26 in half of the years, before November 7 in 9 years out of 10. Typical frost-free season: 200 days.JFMAMJJASONDLast frost ~Apr 8First frost ~Oct 26
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)April 24October 13
50% (typical)April 8October 26
90% (likely)March 25November 7
Frost-free season (32°F, 50% chance)
200 days
Hard frost (28°F), last in spring, 50% chance after
March 30
Hard frost (28°F), first in fall, 50% chance before
November 4

The last 15 years (2006–2020 normals)

Typical last frost April 7 (1 day earlier than the 30-year normal), typical first fall frost October 26. Frost-free season 202 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 Iola: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 24, 20% April 19, 30% April 14, 40% April 11, 50% April 8, 60% April 5, 70% April 2, 80% March 31, 90% March 25. Observed last spring frost in recent years: 2021 April 22, 2022 April 19, 2023 April 23, 2024 April 5, 2025 April 7, 2026 March 18.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 24Apr 8Mar 252021: April 222022: April 192023: April 232024: April 52025: April 72026: March 18Fall at Iola: chance of a frost before this dateFall, chance of a frost before the date: 10% October 13, 20% October 17, 30% October 21, 40% October 23, 50% October 26, 60% October 29, 70% November 1, 80% November 3, 90% November 7. Observed first fall frost in recent years: 2021 November 13, 2022 October 18, 2023 October 30, 2024 October 16, 2025 November 2.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 13Oct 26Nov 72021: November 132022: October 182023: October 302024: October 162025: November 2
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 22November 13
2022April 19October 18
2023April 23October 30
2024April 5October 16
2025April 7November 2
2026March 18season not over yet

What these dates mean

The cautious fall date for finishing the harvest in Iola is October 13, when there is only a 10 % chance that a light frost has arrived.

Gardeners use the 50 % light-frost dates—April 8 in spring and October 26 in fall—to gauge the point at which frost is equally likely to occur or not, but they are not themselves frost dates. The 50 % hard-frost dates are March 30 in spring and November 4 in fall; a hard frost (28 °F) can damage plants more severely than a light frost (32 °F). For a low-risk plan, the cautious spring date is April 24, where a light frost later than that date has only a 10 % chance, and the cautious fall date is October 13, where a light frost earlier than that date has only a 10 % chance.

Because a hard frost can kill tender tissue that survives a light frost, it is a more critical threshold for protecting crops.

How to read the probabilities

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

  • Spring: "10% after April 24" 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 October 13" 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 Iola, KSNumbered nearest stations: 1 — Yates Center, KS — 17 mi; 2 — near Chanute, KS — 18 mi; 3 — Garnett, KS — 27 mi; 4 — Parsons, KS — 39 mi; 5 — Fort Scott, KS — 40 mi.MO25 mi · 40 km1. Yates Center, KS — 17 mi12. near Chanute, KS — 18 mi23. Garnett, KS — 27 mi34. Parsons, KS — 39 mi45. Fort Scott, KS — 40 mi5
  1. Yates Center, KS 17 mi (27 km)
  2. near Chanute, KS 18 mi (29 km)
  3. Garnett, KS 27 mi (44 km)
  4. Parsons, KS 39 mi (63 km)
  5. Fort Scott, KS 40 mi (65 km)

Sources

* Hardiness zone 6b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 37.9233, -95.4242.