U.S. Frost Dates by Weather Station

NOAA station USC00106891 · Idaho

Frost Dates for Payette, ID

NOAA weather station Payette (USC00106891), Idaho · elevation 2150 ft (655 m) · hardiness zone 7a*

  • Lower-risk planting dateafter May 5only 1 spring in 10 still has a frost later
  • Typical last frostApril 1950% chance of a frost after it
  • Typical first fall frostOctober 2050% chance of a frost before it
  • Frost-free season183 daystypical year, 32°F
  • Hardiness zone7acalculated*

The year at a glance

Frost season at Payette, IDSpring: a frost after April 1 in 9 years out of 10, after April 19 in half of the years, after May 5 in 1 year out of 10. Fall: the first frost comes before October 6 in 1 year out of 10, before October 20 in half of the years, before November 4 in 9 years out of 10. Typical frost-free season: 183 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 19First frost ~Oct 20Frost season at Payette, IDSpring: a frost after April 1 in 9 years out of 10, after April 19 in half of the years, after May 5 in 1 year out of 10. Fall: the first frost comes before October 6 in 1 year out of 10, before October 20 in half of the years, before November 4 in 9 years out of 10. Typical frost-free season: 183 days.JFMAMJJASONDLast frost ~Apr 19First frost ~Oct 20
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 5October 6
50% (typical)April 19October 20
90% (likely)April 1November 4
Frost-free season (32°F, 50% chance)
183 days
Hard frost (28°F), last in spring, 50% chance after
March 31
Hard frost (28°F), first in fall, 50% chance before
October 31

The last 15 years (2006–2020 normals)

Typical last frost April 15 (4 days earlier than the 30-year normal), typical first fall frost October 23 (3 days later). Frost-free season 189 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 Payette: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 5, 20% April 30, 30% April 27, 40% April 23, 50% April 19, 60% April 16, 70% April 11, 80% April 7, 90% April 1. Observed last spring frost in recent years: 2021 April 13, 2023 April 20, 2024 April 30, 2025 April 7, 2026 April 29.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 5Apr 19Apr 12021: April 132023: April 202024: April 302025: April 72026: April 29Fall at Payette: chance of a frost before this dateFall, chance of a frost before the date: 10% October 6, 20% October 10, 30% October 14, 40% October 17, 50% October 20, 60% October 23, 70% October 25, 80% October 29, 90% November 4. Observed first fall frost in recent years: 2021 October 16, 2023 October 27, 2024 October 25, 2025 October 21.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 6Oct 20Nov 42021: October 162023: October 272024: October 252025: October 21
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 13October 16
2022incomplete recordincomplete record
2023April 20October 27
2024April 30October 25
2025April 7October 21
2026April 29season not over yet

What these dates mean

October 6 is the cautious fall date in Payette for finishing the harvest of tender crops, with only a 10% chance that a light frost has arrived earlier.

For a gardener, the 50% light-frost dates are April 19 in spring and October 20 in fall; on each of those days there is a 50% chance of a frost later (spring) or earlier (fall). The 50% hard-frost dates are March 31 and October 31, marking an even chance of a 28 °F frost occurring later (spring) or earlier (fall).

May 5 is the cautious spring date for setting out tender crops, with only a 10% chance of a light frost later, while April 1 carries a 90% gamble. A hard frost at 28 °F can damage plants more severely than a light frost at 32 °F, so those median hard-frost dates are especially relevant.

How to read the probabilities

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

  • Spring: "10% after May 5" 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 6" 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 Payette, IDNumbered nearest stations: 1 — Emmett, ID — 28 mi; 2 — Cambridge, ID — 37 mi; 3 — near Hidden Spring, ID — 43 mi; 4 — Garden Valley, ID — 48 mi; 5 — Boise (Air Terminal), ID — 49 mi.OR25 mi · 40 km1. Emmett, ID — 28 mi12. Cambridge, ID — 37 mi23. near Hidden Spring, ID — 43 mi34. Garden Valley, ID — 48 mi45. Boise (Air Terminal), ID — 49 mi5
  1. Emmett, ID 28 mi (45 km)
  2. Cambridge, ID 37 mi (59 km)
  3. near Hidden Spring, ID 43 mi (69 km)
  4. Garden Valley, ID 48 mi (77 km)
  5. Boise (Air Terminal), ID 49 mi (79 km)

Sources

* Hardiness zone 7a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 44.0764, -116.9311.