U.S. Frost Dates by Weather Station

NOAA station USC00205073 · Michigan

Frost Dates for Manistique, MI

NOAA weather station Manistique WWTP (USC00205073), Michigan · elevation 600 ft (183 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 23only 1 spring in 10 still has a frost later
  • Typical last frostMay 950% chance of a frost after it
  • Typical first fall frostOctober 1050% chance of a frost before it
  • Frost-free season154 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Manistique, MISpring: a frost after April 27 in 9 years out of 10, after May 9 in half of the years, after May 23 in 1 year out of 10. Fall: the first frost comes before September 27 in 1 year out of 10, before October 10 in half of the years, before October 27 in 9 years out of 10. Typical frost-free season: 154 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 9First frost ~Oct 10Frost season at Manistique, MISpring: a frost after April 27 in 9 years out of 10, after May 9 in half of the years, after May 23 in 1 year out of 10. Fall: the first frost comes before September 27 in 1 year out of 10, before October 10 in half of the years, before October 27 in 9 years out of 10. Typical frost-free season: 154 days.JFMAMJJASONDLast frost ~May 9First frost ~Oct 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 30 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 23September 27
50% (typical)May 9October 10
90% (likely)April 27October 27
Frost-free season (32°F, 50% chance)
154 days
Hard frost (28°F), last in spring, 50% chance after
April 27
Hard frost (28°F), first in fall, 50% chance before
October 26

The last 15 years (2006–2020 normals)

Typical last frost May 9 (same as the 30-year normal), typical first fall frost October 14 (4 days later). Frost-free season 155 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 Manistique: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 23, 20% May 19, 30% May 15, 40% May 12, 50% May 9, 60% May 6, 70% May 3, 80% April 30, 90% April 27. Observed last spring frost in recent years: 2021 May 12, 2022 May 4, 2023 May 17, 2024 April 26, 2025 May 9, 2026 May 21.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 23May 9Apr 272021: May 122022: May 42023: May 172024: April 262025: May 92026: May 21Fall at Manistique: chance of a frost before this dateFall, chance of a frost before the date: 10% September 27, 20% October 2, 30% October 5, 40% October 8, 50% October 10, 60% October 13, 70% October 17, 80% October 21, 90% October 27. Observed first fall frost in recent years: 2021 October 24, 2022 October 8, 2023 October 23, 2024 October 10, 2025 October 25.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 27Oct 10Oct 272021: October 242022: October 82023: October 232024: October 102025: 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 12October 24
2022May 4October 8
2023May 17October 23
2024April 26October 10
2025May 9October 25
2026May 21season not over yet

What these dates mean

The 154 days between the 50% dates in Manistique, May 9 and October 10, hold the span when average temperatures typically stay above the light-frost threshold.

The 50% date of May 9 carries a 50 % chance of a frost later, while the 50% date of October 10 carries a 50 % chance of a frost earlier. Gardeners who prefer a cautious approach would wait until the May 23 date, which carries only a 10 % chance of a later frost, to set out tender crops, and would aim to finish harvesting tender crops by the September 27 date, which carries only a 10 % chance of an earlier frost.

The 50% hard-frost dates are April 27 and October 26, marking the midpoint of risk for temperatures dropping to 28 °F, and a hard frost at 28 °F can damage plants more severely than a light frost at 32 °F.

How to read the probabilities

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

  • Spring: "10% after May 23" 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 27" 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 Manistique, MINumbered nearest stations: 1 — Munising, MI — 37 mi; 2 — St. James 4 SSW Beaver, MI — 38 mi; 3 — Chatham Experiment Farm 2, MI — 42 mi; 4 — Washington Island, WI — 51 mi; 5 — Cross Village, MI — 63 mi.MI25 mi · 40 km1. Munising, MI — 37 mi12. St. James 4 SSW Beaver, MI — 38 mi23. Chatham Experiment Farm 2, MI — 42 mi34. Washington Island, WI — 51 mi45. Cross Village, MI — 63 mi5
  1. Munising, MI 37 mi (60 km)
  2. St. James 4 SSW Beaver, MI 38 mi (62 km)
  3. Chatham Experiment Farm 2, MI 42 mi (68 km)
  4. Washington Island, WI 51 mi (83 km)
  5. Cross Village, MI 63 mi (102 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: 45.9511, -86.2514.