U.S. Frost Dates by Weather Station

NOAA station USC00207277 · Michigan

Frost Dates for St. James 4 SSW Beaver, MI

NOAA weather station St. James 4 SSW Beaver (USC00207277), Michigan · elevation 672 ft (205 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 26only 1 spring in 10 still has a frost later
  • Typical last frostMay 1150% chance of a frost after it
  • Typical first fall frostOctober 1950% chance of a frost before it
  • Frost-free season159 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at St. James 4 SSW Beaver, MISpring: a frost after April 27 in 9 years out of 10, after May 11 in half of the years, after May 26 in 1 year out of 10. Fall: the first frost comes before October 2 in 1 year out of 10, before October 19 in half of the years, before November 3 in 9 years out of 10. Typical frost-free season: 159 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 11First frost ~Oct 19Frost season at St. James 4 SSW Beaver, MISpring: a frost after April 27 in 9 years out of 10, after May 11 in half of the years, after May 26 in 1 year out of 10. Fall: the first frost comes before October 2 in 1 year out of 10, before October 19 in half of the years, before November 3 in 9 years out of 10. Typical frost-free season: 159 days.JFMAMJJASONDLast frost ~May 11First frost ~Oct 19
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 26October 2
50% (typical)May 11October 19
90% (likely)April 27November 3
Frost-free season (32°F, 50% chance)
159 days
Hard frost (28°F), last in spring, 50% chance after
April 30
Hard frost (28°F), first in fall, 50% chance before
November 2

The last 15 years (2006–2020 normals)

Typical last frost May 12 (1 day later than the 30-year normal), typical first fall frost October 25 (6 days later). Frost-free season 163 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 St. James 4 SSW Beaver: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 26, 20% May 22, 30% May 18, 40% May 14, 50% May 11, 60% May 8, 70% May 5, 80% May 1, 90% April 27. Observed last spring frost in recent years: 2021 May 12, 2022 April 29, 2023 May 4, 2024 April 25, 2025 May 9, 2026 May 21.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 26May 11Apr 272021: May 122022: April 292023: May 42024: April 252025: May 92026: May 21Fall at St. James 4 SSW Beaver: chance of a frost before this dateFall, chance of a frost before the date: 10% October 2, 20% October 7, 30% October 11, 40% October 15, 50% October 19, 60% October 22, 70% October 25, 80% October 29, 90% November 3. Observed first fall frost in recent years: 2021 November 3, 2022 October 10, 2023 October 30, 2024 November 2, 2025 October 25.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 2Oct 19Nov 32021: November 32022: October 102023: October 302024: November 22025: October 25
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 12November 3
2022April 29October 10
2023May 4October 30
2024April 25November 2
2025May 9October 25
2026May 21season not over yet

What these dates mean

May 26 is the cautious spring date, giving a gardener only a 10% chance that a light frost will occur later, so tender crops can be set out with minimal risk. The 50% date of May 11 marks the point where the odds of a light frost later are even, and the hard-frost median of April 30 signals when a 28 °F freeze becomes a 50-50 prospect, which matters more because a hard frost can damage plants that survive a light frost.

In the fall, October 2 is the cautious date for finishing harvest of tender crops, carrying only a 10% chance that a light frost has already arrived. The 50% date of October 19 shows equal odds of a frost occurring earlier, while the hard-frost median of November 2 indicates when a 28 °F freeze becomes equally likely, and hard frost is more destructive than a light frost.

How to read the probabilities

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

  • Spring: "10% after May 26" 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 St. James 4 SSW Beaver, MINumbered nearest stations: 1 — Cross Village, MI — 26 mi; 2 — Petoskey, MI — 35 mi; 3 — Pellston, MI — 37 mi; 4 — Manistique, MI — 38 mi; 5 — near Boyne City, MI — 47 mi.25 mi · 40 km1. Cross Village, MI — 26 mi12. Petoskey, MI — 35 mi23. Pellston, MI — 37 mi34. Manistique, MI — 38 mi45. near Boyne City, MI — 47 mi5
  1. Cross Village, MI 26 mi (42 km)
  2. Petoskey, MI 35 mi (57 km)
  3. Pellston, MI 37 mi (60 km)
  4. Manistique, MI 38 mi (62 km)
  5. near Boyne City, MI 47 mi (76 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: 45.6911, -85.5464.