U.S. Frost Dates by Weather Station

NOAA station USC00204257 · Michigan

Frost Dates for Kalkaska, MI

NOAA weather station Kalkaska (USC00204257), Michigan · elevation 1035 ft (316 m) · hardiness zone 5a*

  • Lower-risk planting dateafter June 7only 1 spring in 10 still has a frost later
  • Typical last frostMay 2450% chance of a frost after it
  • Typical first fall frostOctober 150% chance of a frost before it
  • Frost-free season128 daystypical year, 32°F
  • Hardiness zone5acalculated*

The year at a glance

Frost season at Kalkaska, MISpring: a frost after May 7 in 9 years out of 10, after May 24 in half of the years, after June 7 in 1 year out of 10. Fall: the first frost comes before September 14 in 1 year out of 10, before October 1 in half of the years, before October 14 in 9 years out of 10. Typical frost-free season: 128 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 24First frost ~Oct 1Frost season at Kalkaska, MISpring: a frost after May 7 in 9 years out of 10, after May 24 in half of the years, after June 7 in 1 year out of 10. Fall: the first frost comes before September 14 in 1 year out of 10, before October 1 in half of the years, before October 14 in 9 years out of 10. Typical frost-free season: 128 days.JFMAMJJASONDLast frost ~May 24First frost ~Oct 1
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)June 7September 14
50% (typical)May 24October 1
90% (likely)May 7October 14
Frost-free season (32°F, 50% chance)
128 days
Hard frost (28°F), last in spring, 50% chance after
May 10
Hard frost (28°F), first in fall, 50% chance before
October 12

The last 15 years (2006–2020 normals)

Typical last frost May 22 (2 days earlier than the 30-year normal), typical first fall frost October 2 (1 day later). Frost-free season 132 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 Kalkaska: chance of a frost after this dateSpring, chance of a frost after the date: 10% June 7, 20% June 2, 30% May 30, 40% May 27, 50% May 24, 60% May 22, 70% May 18, 80% May 14, 90% May 7. Observed last spring frost in recent years: 2021 May 31, 2022 May 24, 2023 May 26, 2024 April 26, 2025 June 2, 2026 May 21.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1Jun 7May 24May 72021: May 312022: May 242023: May 262024: April 262025: June 22026: May 21Fall at Kalkaska: chance of a frost before this dateFall, chance of a frost before the date: 10% September 14, 20% September 20, 30% September 24, 40% September 27, 50% October 1, 60% October 2, 70% October 5, 80% October 8, 90% October 14. Observed first fall frost in recent years: 2021 October 18, 2022 September 23, 2023 September 19, 2024 October 5, 2025 October 8.Fall: first frostChance of a frost before this date10%50%90%Sep 1Oct 1Sep 14Oct 1Oct 142021: October 182022: September 232023: September 192024: October 52025: October 8
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 31October 18
2022May 24September 23
2023May 26September 19
2024April 26October 5
2025June 2October 8
2026May 21season not over yet

What these dates mean

Setting out tender crops on the early spring date risks a 90 % chance of a light frost; the date is May 7. In Kalkaska this early timing is a gamble for sensitive plants.

A cautious spring plan would wait until June 7, when only a 10 % chance of a light frost remains. For the autumn harvest, the cautious date to finish tender crops is September 14, with a 10 % chance that a light frost has already arrived; extending planting to October 14 carries a 90 % chance of a light frost and is therefore a gamble.

The 50 % light-frost dates are May 24 in spring and October 1 in fall; each marks the point where a light frost is equally likely to have occurred or not. The 50 % hard-frost dates are May 10 and October 12, and hard frost at 28 °F can damage plant tissue that survives a light frost at 32 °F, making it a more critical threshold for gardeners.

How to read the probabilities

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

  • Spring: "10% after June 7" 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 14" 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 Kalkaska, MINumbered nearest stations: 1 — near Traverse City, MI — 20 mi; 2 — Grayling, MI — 24 mi; 3 — Lake City, MI — 29 mi; 4 — Gaylord, MI — 31 mi; 5 — near Boyne City, MI — 33 mi.25 mi · 40 km1. near Traverse City, MI — 20 mi12. Grayling, MI — 24 mi23. Lake City, MI — 29 mi34. Gaylord, MI — 31 mi45. near Boyne City, MI — 33 mi5
  1. near Traverse City, MI 20 mi (32 km)
  2. Grayling, MI 24 mi (38 km)
  3. Lake City, MI 29 mi (47 km)
  4. Gaylord, MI 31 mi (50 km)
  5. near Boyne City, MI 33 mi (53 km)

Sources

* Hardiness zone 5a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 44.7281, -85.1728.