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 dates (32°F)
| Chance | Last frost in spring after | First frost in fall before |
|---|---|---|
| 10% (unlikely) | May 22 | September 29 |
| 50% (typical) | May 3 | October 12 |
| 90% (likely) | April 20 | October 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
What actually happened in recent years
| Year | Last spring frost | First fall frost |
|---|---|---|
| 2021 | May 30 | October 24 |
| 2022 | April 29 | October 3 |
| 2023 | May 27 | October 23 |
| 2024 | April 26 | October 17 |
| 2025 | May 10 | October 25 |
| 2026 | incomplete record | season 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
- Grand Rapids, MI 22 mi (35 km)
- Charlotte, MI 24 mi (39 km)
- near Lansing, MI 37 mi (60 km)
- near Jackson, MI 49 mi (79 km)
- near Coldwater, MI 49 mi (79 km)
Sources
- NOAA NCEI U.S. Climate Normals 1991–2020, station USC00203661
- NOAA NCEI U.S. Climate Normals
- PRISM Group, Oregon State University — 2023 USDA Plant Hardiness Zone GIS datasets
- NOAA NCEI U.S. Climate Normals 2006–2020 (15-year normals), station USC00203661
- NOAA NCEI Global Historical Climatology Network – Daily (GHCN-Daily), observed daily minimum temperature, retrieved 2026-10-08
* 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.