U.S. Frost Dates by Weather Station

NOAA station USC00203661 · Michigan

Frost Dates for Hastings, MI

NOAA weather station Hastings (USC00203661), Michigan · elevation 821 ft (250 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 22only 1 spring in 10 still has a frost later
  • Typical last frostMay 350% chance of a frost after it
  • Typical first fall frostOctober 1250% chance of a frost before it
  • Frost-free season158 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Hastings, MISpring: a frost after April 20 in 9 years out of 10, after May 3 in half of the years, after May 22 in 1 year out of 10. Fall: the first frost comes before September 29 in 1 year out of 10, before October 12 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 158 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 3First frost ~Oct 12Frost season at Hastings, MISpring: a frost after April 20 in 9 years out of 10, after May 3 in half of the years, after May 22 in 1 year out of 10. Fall: the first frost comes before September 29 in 1 year out of 10, before October 12 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 158 days.JFMAMJJASONDLast frost ~May 3First frost ~Oct 12
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 22September 29
50% (typical)May 3October 12
90% (likely)April 20October 28
Frost-free season (32°F, 50% chance)
158 days
Hard frost (28°F), last in spring, 50% chance after
April 24
Hard frost (28°F), first in fall, 50% chance before
October 26

The last 15 years (2006–2020 normals)

Typical last frost May 3 (same as the 30-year normal), typical first fall frost October 17 (5 days later). Frost-free season 164 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 Hastings: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 22, 20% May 15, 30% May 11, 40% May 7, 50% May 3, 60% May 1, 70% April 29, 80% April 25, 90% April 20. Observed last spring frost in recent years: 2021 May 30, 2022 April 29, 2023 May 27, 2024 April 26, 2025 May 10.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 22May 3Apr 202021: May 302022: April 292023: May 272024: April 262025: May 10Fall at Hastings: chance of a frost before this dateFall, chance of a frost before the date: 10% September 29, 20% October 2, 30% October 6, 40% October 9, 50% October 12, 60% October 15, 70% October 19, 80% October 22, 90% October 28. Observed first fall frost in recent years: 2021 October 24, 2022 October 3, 2023 October 23, 2024 October 17, 2025 October 25.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 29Oct 12Oct 282021: October 242022: October 32023: October 232024: October 172025: 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 30October 24
2022April 29October 3
2023May 27October 23
2024April 26October 17
2025May 10October 25
2026incomplete recordseason not over yet

What these dates mean

The 158 days between the 50% dates in Hastings, Michigan, span the window when tender crops can generally be grown. The 50% date in spring is May 3; there is a 50% chance of a light frost later than this date. The 50% date in fall is October 12; there is a 50% chance of a light frost earlier than this date. The median hard-frost dates are April 24 in spring and October 26 in fall.

In spring the cautious date for setting out tender crops is May 22, when the chance of a later light frost has dropped to 10%; planting on April 20 would be a gamble with a 90% chance of frost. In fall the cautious date to finish harvesting tender crops is September 29, when only a 10% chance a light frost has arrived earlier; waiting until October 28 would be a gamble with a 90% chance of frost. A hard frost at 28 °F can damage plants that survive a light frost at 32 °F, making it the more critical temperature threshold.

How to read the probabilities

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

  • Spring: "10% after May 22" 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 29" 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 Hastings, MINumbered nearest stations: 1 — Grand Rapids, MI — 22 mi; 2 — Charlotte, MI — 24 mi; 3 — near Lansing, MI — 37 mi; 4 — near Jackson, MI — 49 mi; 5 — near Coldwater, MI — 49 mi.OH25 mi · 40 km1. Grand Rapids, MI — 22 mi12. Charlotte, MI — 24 mi23. near Lansing, MI — 37 mi34. near Jackson, MI — 49 mi45. near Coldwater, MI — 49 mi5
  1. Grand Rapids, MI 22 mi (35 km)
  2. Charlotte, MI 24 mi (39 km)
  3. near Lansing, MI 37 mi (60 km)
  4. near Jackson, MI 49 mi (79 km)
  5. near Coldwater, MI 49 mi (79 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: 42.6419, -85.2881.