U.S. Frost Dates by Weather Station

NOAA station USC00145856 · Kansas

Frost Dates for Norton, KS

NOAA weather station Norton 9 SSE (USC00145856), Kansas · elevation 2413 ft (736 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 11only 1 spring in 10 still has a frost later
  • Typical last frostApril 2750% chance of a frost after it
  • Typical first fall frostOctober 1750% chance of a frost before it
  • Frost-free season173 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Norton, KSSpring: a frost after April 12 in 9 years out of 10, after April 27 in half of the years, after May 11 in 1 year out of 10. Fall: the first frost comes before October 1 in 1 year out of 10, before October 17 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 173 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 27First frost ~Oct 17Frost season at Norton, KSSpring: a frost after April 12 in 9 years out of 10, after April 27 in half of the years, after May 11 in 1 year out of 10. Fall: the first frost comes before October 1 in 1 year out of 10, before October 17 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 173 days.JFMAMJJASONDLast frost ~Apr 27First frost ~Oct 17
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 11October 1
50% (typical)April 27October 17
90% (likely)April 12October 28
Frost-free season (32°F, 50% chance)
173 days
Hard frost (28°F), last in spring, 50% chance after
April 15
Hard frost (28°F), first in fall, 50% chance before
October 25

The last 15 years (2006–2020 normals)

Typical last frost April 27 (same as the 30-year normal), typical first fall frost October 18 (1 day later). Frost-free season 173 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 Norton: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 11, 20% May 5, 30% May 2, 40% April 30, 50% April 27, 60% April 23, 70% April 19, 80% April 16, 90% April 12. Observed last spring frost in recent years: 2025 April 20, 2026 April 29.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 11Apr 27Apr 122025: April 202026: April 29Fall at Norton: chance of a frost before this dateFall, chance of a frost before the date: 10% October 1, 20% October 6, 30% October 11, 40% October 14, 50% October 17, 60% October 19, 70% October 22, 80% October 25, 90% October 28. Observed first fall frost in recent years: 2025 October 29.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 1Oct 17Oct 282025: October 29
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
2021incomplete recordincomplete record
2022incomplete recordincomplete record
2023incomplete recordno data
2024no dataincomplete record
2025April 20October 29
2026April 29season not over yet

What these dates mean

The 173 days between the 32°F 50% dates of April 27 and October 17 frame the core growing window in Norton. During that span a gardener faces an even chance of a light frost on either side of the median, while the hard-frost 50% dates of April 15 and October 25 mark when a 28°F event is as likely as not, a temperature that can damage plant tissue more severely than a 32°F light frost.

To reduce risk, the cautious spring date for setting out tender crops is May 11, when only a 10% chance of a later light frost remains; planting on April 12 carries a 90% chance and is a gamble. In the fall the cautious date to finish harvesting tender crops is October 1, with a 10% chance that a light frost has already arrived, while extending to October 28 involves a 90% chance of an early frost. Because a hard frost at 28°F can injure or kill tender growth more readily than a light frost, it is the more critical temperature threshold for gardeners.

How to read the probabilities

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

  • Spring: "10% after May 11" 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 1" 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 Norton, KSNumbered nearest stations: 1 — Norton Dam, KS — 7 mi; 2 — Beaver City, NE — 27 mi; 3 — Cambridge, NE — 41 mi; 4 — Plainville, KS — 42 mi; 5 — Wakeeney, KS — 50 mi.KS25 mi · 40 km1. Norton Dam, KS — 7 mi12. Beaver City, NE — 27 mi23. Cambridge, NE — 41 mi34. Plainville, KS — 42 mi45. Wakeeney, KS — 50 mi5
  1. Norton Dam, KS 7 mi (12 km)
  2. Beaver City, NE 27 mi (43 km)
  3. Cambridge, NE 41 mi (66 km)
  4. Plainville, KS 42 mi (68 km)
  5. Wakeeney, KS 50 mi (81 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: 39.7408, -99.8361.