U.S. Frost Dates by Weather Station

NOAA station USC00207812 · Michigan

Frost Dates for Stambaugh, MI

NOAA weather station Stambaugh 2 SSE (USC00207812), Michigan · elevation 1450 ft (442 m) · hardiness zone 4a*

  • Lower-risk planting dateafter June 26only 1 spring in 10 still has a frost later
  • Typical last frostJune 450% chance of a frost after it
  • Typical first fall frostSeptember 1050% chance of a frost before it
  • Frost-free season95 daystypical year, 32°F
  • Hardiness zone4acalculated*

The year at a glance

Frost season at Stambaugh, MISpring: a frost after May 22 in 9 years out of 10, after June 4 in half of the years, after June 26 in 1 year out of 10. Fall: the first frost comes before August 21 in 1 year out of 10, before September 10 in half of the years, before September 25 in 9 years out of 10. Typical frost-free season: 95 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Jun 4First frost ~Sep 10Frost season at Stambaugh, MISpring: a frost after May 22 in 9 years out of 10, after June 4 in half of the years, after June 26 in 1 year out of 10. Fall: the first frost comes before August 21 in 1 year out of 10, before September 10 in half of the years, before September 25 in 9 years out of 10. Typical frost-free season: 95 days.JFMAMJJASONDLast frost ~Jun 4First frost ~Sep 10
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)June 26August 21
50% (typical)June 4September 10
90% (likely)May 22September 25
Frost-free season (32°F, 50% chance)
95 days
Hard frost (28°F), last in spring, 50% chance after
May 23
Hard frost (28°F), first in fall, 50% chance before
September 24

The last 15 years (2006–2020 normals)

Typical last frost June 6 (2 days later than the 30-year normal), typical first fall frost September 6 (4 days earlier). Frost-free season 90 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 Stambaugh: chance of a frost after this dateSpring, chance of a frost after the date: 10% June 26, 20% June 18, 30% June 12, 40% June 8, 50% June 4, 60% June 1, 70% May 30, 80% May 26, 90% May 22. Observed last spring frost in recent years: 2021 May 30, 2022 June 4, 2023 June 12, 2024 June 11, 2025 June 1, 2026 May 22.Spring: last frostChance of a frost after this date10%50%90%Jun 1Jul 1Jun 26Jun 4May 222021: May 302022: June 42023: June 122024: June 112025: June 12026: May 22Fall at Stambaugh: chance of a frost before this dateFall, chance of a frost before the date: 10% August 21, 20% August 29, 30% September 3, 40% September 6, 50% September 10, 60% September 13, 70% September 17, 80% September 20, 90% September 25. Observed first fall frost in recent years: 2021 September 18, 2022 September 23, 2023 October 8, 2024 September 22, 2025 October 7.Fall: first frostChance of a frost before this date10%50%90%Sep 1Oct 1Aug 21Sep 10Sep 252021: September 182022: September 232023: October 82024: September 222025: October 7
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 30September 18
2022June 4September 23
2023June 12October 8
2024June 11September 22
2025June 1October 7
2026May 22season not over yet

What these dates mean

June 26 is the cautious spring date for Stambaugh; with only a 10 % chance of a light frost after that day, a gardener can plan to set out tender crops then. The counterpart cautious fall date is August 21, when there is just a 10 % chance that a light frost has already arrived, marking a point to finish harvesting tender crops. The 50 % light-frost dates are June 4 and September 10; at each of those dates the odds of a frost occurring later (spring) or earlier (fall) are even, giving a clear reference for when risk balances out.

Hard-frost risk is shown by the 50 % dates of May 23 and September 24, and a hard frost at 28 °F can damage plants that would survive a 32 °F light frost. Gardeners can use these points to gauge the narrow window between the two 32 °F median dates, which spans 95 days.

How to read the probabilities

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

  • Spring: "10% after June 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 August 21" 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 Stambaugh, MINumbered nearest stations: 1 — near Kingsford, MI — 32 mi; 2 — Bergland Dam, MI — 57 mi; 3 — Marquette (USW00094850), MI — 61 mi; 4 — Marquette (USW00014838), MI — 69 mi; 5 — Hancock, MI — 77 mi.MIWI25 mi · 40 km1. near Kingsford, MI — 32 mi12. Bergland Dam, MI — 57 mi23. Marquette (USW00094850), MI — 61 mi34. Marquette (USW00014838), MI — 69 mi45. Hancock, MI — 77 mi5
  1. near Kingsford, MI 32 mi (52 km)
  2. Bergland Dam, MI 57 mi (92 km)
  3. Marquette (USW00094850), MI 61 mi (98 km)
  4. Marquette (USW00014838), MI 69 mi (110 km)
  5. Hancock, MI 77 mi (124 km)

Sources

* Hardiness zone 4a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 46.0556, -88.6275.