U.S. Frost Dates by Weather Station

NOAA station USC00206507 · Michigan

Frost Dates for Petoskey, MI

NOAA weather station Petoskey (USC00206507), Michigan · elevation 599 ft (183 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 21only 1 spring in 10 still has a frost later
  • Typical last frostMay 650% chance of a frost after it
  • Typical first fall frostOctober 2050% chance of a frost before it
  • Frost-free season166 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Petoskey, MISpring: a frost after April 23 in 9 years out of 10, after May 6 in half of the years, after May 21 in 1 year out of 10. Fall: the first frost comes before October 2 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: 166 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 6First frost ~Oct 20Frost season at Petoskey, MISpring: a frost after April 23 in 9 years out of 10, after May 6 in half of the years, after May 21 in 1 year out of 10. Fall: the first frost comes before October 2 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: 166 days.JFMAMJJASONDLast frost ~May 6First 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 28 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 21October 2
50% (typical)May 6October 20
90% (likely)April 23November 4
Frost-free season (32°F, 50% chance)
166 days
Hard frost (28°F), last in spring, 50% chance after
April 23
Hard frost (28°F), first in fall, 50% chance before
November 3

The last 15 years (2006–2020 normals)

Typical last frost May 4 (2 days earlier than the 30-year normal), typical first fall frost October 23 (3 days later). Frost-free season 170 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 Petoskey: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 21, 20% May 16, 30% May 12, 40% May 9, 50% May 6, 60% May 3, 70% April 30, 80% April 28, 90% April 23. Observed last spring frost in recent years: 2021 May 9, 2022 April 29, 2023 April 27, 2024 April 26, 2025 May 1, 2026 May 12.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 21May 6Apr 232021: May 92022: April 292023: April 272024: April 262025: May 12026: May 12Fall at Petoskey: chance of a frost before this dateFall, chance of a frost before the date: 10% October 2, 20% October 6, 30% October 11, 40% October 16, 50% October 20, 60% October 23, 70% October 27, 80% October 30, 90% November 4. Observed first fall frost in recent years: 2021 October 22, 2022 October 10, 2023 October 31, 2024 November 2, 2025 October 30.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 2Oct 20Nov 42021: October 222022: October 102023: October 312024: November 22025: October 30
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 9October 22
2022April 29October 10
2023April 27October 31
2024April 26November 2
2025May 1October 30
2026May 12season not over yet

What these dates mean

May 21 marks the cautious spring light-frost date for Petoskey; with only a 10 % chance of a frost later, a gardener can plan to set out tender crops after this point. The 50% date is May 6, indicating a 50 % chance of a frost later than this date, and the 50% date is October 20, indicating a 50 % chance of a frost earlier than this date. October 2 is the cautious fall light-frost date, carrying only a 10 % chance that a frost has arrived earlier, which lets a gardener finish harvesting tender crops. The 50% hard-frost dates are April 23 and November 3. A hard frost at 28 °F matters more than a light frost at 32 °F because it can kill plant tissue that would survive the milder temperature.

How to read the probabilities

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

  • Spring: "10% after May 21" 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 2" 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 Petoskey, MINumbered nearest stations: 1 — near Boyne City, MI — 15 mi; 2 — Pellston, MI — 16 mi; 3 — Cross Village, MI — 19 mi; 4 — Gaylord, MI — 27 mi; 5 — Vanderbilt, MI — 30 mi.25 mi · 40 km1. near Boyne City, MI — 15 mi12. Pellston, MI — 16 mi23. Cross Village, MI — 19 mi34. Gaylord, MI — 27 mi45. Vanderbilt, MI — 30 mi5
  1. near Boyne City, MI 15 mi (23 km)
  2. Pellston, MI 16 mi (26 km)
  3. Cross Village, MI 19 mi (30 km)
  4. Gaylord, MI 27 mi (43 km)
  5. Vanderbilt, MI 30 mi (48 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: 45.3725, -84.9767.