U.S. Frost Dates by Weather Station

NOAA station USC00205567 · Michigan

Frost Dates for Montague, MI

NOAA weather station Montague 4 NW (USC00205567), Michigan · elevation 650 ft (198 m) · hardiness zone 6a*

  • Lower-risk planting dateafter June 6only 1 spring in 10 still has a frost later
  • Typical last frostMay 1950% chance of a frost after it
  • Typical first fall frostOctober 450% chance of a frost before it
  • Frost-free season136 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Montague, MISpring: a frost after May 1 in 9 years out of 10, after May 19 in half of the years, after June 6 in 1 year out of 10. Fall: the first frost comes before September 16 in 1 year out of 10, before October 4 in half of the years, before October 20 in 9 years out of 10. Typical frost-free season: 136 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 19First frost ~Oct 4Frost season at Montague, MISpring: a frost after May 1 in 9 years out of 10, after May 19 in half of the years, after June 6 in 1 year out of 10. Fall: the first frost comes before September 16 in 1 year out of 10, before October 4 in half of the years, before October 20 in 9 years out of 10. Typical frost-free season: 136 days.JFMAMJJASONDLast frost ~May 19First frost ~Oct 4
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 27 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)June 6September 16
50% (typical)May 19October 4
90% (likely)May 1October 20
Frost-free season (32°F, 50% chance)
136 days
Hard frost (28°F), last in spring, 50% chance after
May 5
Hard frost (28°F), first in fall, 50% chance before
October 18

The last 15 years (2006–2020 normals)

Typical last frost May 17 (2 days earlier than the 30-year normal), typical first fall frost October 10 (6 days later). Frost-free season 146 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 Montague: chance of a frost after this dateSpring, chance of a frost after the date: 10% June 6, 20% May 31, 30% May 27, 40% May 23, 50% May 19, 60% May 15, 70% May 11, 80% May 7, 90% May 1. Observed last spring frost in recent years: 2021 May 14, 2022 May 23, 2023 May 15, 2024 April 25, 2025 May 9, 2026 May 14.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1Jun 6May 19May 12021: May 142022: May 232023: May 152024: April 252025: May 92026: May 14Fall at Montague: chance of a frost before this dateFall, chance of a frost before the date: 10% September 16, 20% September 22, 30% September 27, 40% October 1, 50% October 4, 60% October 7, 70% October 10, 80% October 15, 90% October 20. Observed first fall frost in recent years: 2021 October 24, 2022 September 29, 2023 October 17, 2024 October 17, 2025 October 24.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 16Oct 4Oct 202021: October 242022: September 292023: October 172024: October 172025: October 24
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 14October 24
2022May 23September 29
2023May 15October 17
2024April 25October 17
2025May 9October 24
2026May 14season not over yet

What these dates mean

June 6 is the cautious spring date, with only a 10 % chance of a light frost later, and it lets a gardener set out tender crops with confidence.

The 50 % date of May 19 marks the point where a light frost has an even chance of occurring after that day, while October 4 is the 50 % fall date where a light frost has an even chance of arriving earlier. September 16 is the cautious fall date, offering just a 10 % chance that a light frost has already arrived and allowing tender crops to be harvested safely. The 50 % hard-frost dates are May 5 in spring and October 18 in fall, and a hard frost can cause far greater damage to plants than a 32 °F light frost.

These probabilities are drawn from 27 years of NOAA records for Montague, Michigan.

How to read the probabilities

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

  • Spring: "10% after June 6" 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 September 16" 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 Montague, MINumbered nearest stations: 1 — near Norton Shores, MI — 22 mi; 2 — Big Rapids, MI — 50 mi; 3 — Manistee, MI — 52 mi; 4 — Grand Rapids, MI — 59 mi; 5 — Two Rivers, WI — 74 mi.MIWI25 mi · 40 km1. near Norton Shores, MI — 22 mi12. Big Rapids, MI — 50 mi23. Manistee, MI — 52 mi34. Grand Rapids, MI — 59 mi45. Two Rivers, WI — 74 mi5
  1. near Norton Shores, MI 22 mi (35 km)
  2. Big Rapids, MI 50 mi (80 km)
  3. Manistee, MI 52 mi (84 km)
  4. Grand Rapids, MI 59 mi (95 km)
  5. Two Rivers, WI 74 mi (119 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: 43.4614, -86.4175.