U.S. Frost Dates by Weather Station

NOAA station USC00200417 · Michigan

Frost Dates for Bad Axe, MI

NOAA weather station Bad Axe (USC00200417), Michigan · elevation 715 ft (218 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 20only 1 spring in 10 still has a frost later
  • Typical last frostMay 550% chance of a frost after it
  • Typical first fall frostOctober 1950% chance of a frost before it
  • Frost-free season163 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Bad Axe, MISpring: a frost after April 22 in 9 years out of 10, after May 5 in half of the years, after May 20 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: 163 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 5First frost ~Oct 19Frost season at Bad Axe, MISpring: a frost after April 22 in 9 years out of 10, after May 5 in half of the years, after May 20 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: 163 days.JFMAMJJASONDLast frost ~May 5First 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 28 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 20October 2
50% (typical)May 5October 19
90% (likely)April 22November 3
Frost-free season (32°F, 50% chance)
163 days
Hard frost (28°F), last in spring, 50% chance after
April 24
Hard frost (28°F), first in fall, 50% chance before
November 1

The last 15 years (2006–2020 normals)

Typical last frost May 5 (same as the 30-year normal), typical first fall frost October 22 (3 days later). Frost-free season 169 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 Bad Axe: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 20, 20% May 15, 30% May 11, 40% May 8, 50% May 5, 60% May 2, 70% April 30, 80% April 26, 90% April 22. Observed last spring frost in recent years: 2021 May 7, 2022 April 30, 2023 May 19, 2024 April 26, 2025 May 9, 2026 May 13.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 20May 5Apr 222021: May 72022: April 302023: May 192024: April 262025: May 92026: May 13Fall at Bad Axe: 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 28, 2023 October 23, 2024 October 17, 2025 October 26.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 2Oct 19Nov 32021: November 32022: October 282023: October 232024: October 172025: October 26
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 7November 3
2022April 30October 28
2023May 19October 23
2024April 26October 17
2025May 9October 26
2026May 13season not over yet

What these dates mean

The 163 days between the 50% dates of May 5 and October 19 define the span in Bad Axe when light-freeze risk is balanced; within that interval gardeners can expect a roughly even chance that a 32 °F frost will have occurred or not. The median spring date, May 5, and the median fall date, October 19, are not frost thresholds but simply the points at which the probability is 50 %.

A cautious spring plan uses the May 20 date, which carries a 10 % chance that a light frost will appear later, while a cautious fall plan finishes tender-crop work by October 2, when there is only a 10 % chance a light frost has arrived earlier. The hard-frost median dates are April 24 in spring and November 1 in fall; a 28 °F hard frost can damage plants more severely than a 32 °F 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 20" 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 Bad Axe, MINumbered nearest stations: 1 — Harbor Beach, MI — 18 mi; 2 — East Tawas, MI — 41 mi; 3 — Standish, MI — 47 mi; 4 — near Saginaw, MI — 57 mi; 5 — Hale Loud Dam, MI — 58 mi.25 mi · 40 km1. Harbor Beach, MI — 18 mi12. East Tawas, MI — 41 mi23. Standish, MI — 47 mi34. near Saginaw, MI — 57 mi45. Hale Loud Dam, MI — 58 mi5
  1. Harbor Beach, MI 18 mi (28 km)
  2. East Tawas, MI 41 mi (67 km)
  3. Standish, MI 47 mi (76 km)
  4. near Saginaw, MI 57 mi (93 km)
  5. Hale Loud Dam, MI 58 mi (93 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: 43.8081, -82.9939.