U.S. Frost Dates by Weather Station

NOAA station USC00210252 · Minnesota

Frost Dates for Argyle, MN

NOAA weather station Argyle (USC00210252), Minnesota · elevation 847 ft (258 m) · hardiness zone 4a*

  • Lower-risk planting dateafter May 28only 1 spring in 10 still has a frost later
  • Typical last frostMay 1550% chance of a frost after it
  • Typical first fall frostSeptember 2650% chance of a frost before it
  • Frost-free season134 daystypical year, 32°F
  • Hardiness zone4acalculated*

The year at a glance

Frost season at Argyle, MNSpring: a frost after May 1 in 9 years out of 10, after May 15 in half of the years, after May 28 in 1 year out of 10. Fall: the first frost comes before September 13 in 1 year out of 10, before September 26 in half of the years, before October 8 in 9 years out of 10. Typical frost-free season: 134 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 15First frost ~Sep 26Frost season at Argyle, MNSpring: a frost after May 1 in 9 years out of 10, after May 15 in half of the years, after May 28 in 1 year out of 10. Fall: the first frost comes before September 13 in 1 year out of 10, before September 26 in half of the years, before October 8 in 9 years out of 10. Typical frost-free season: 134 days.JFMAMJJASONDLast frost ~May 15First frost ~Sep 26
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 29 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 28September 13
50% (typical)May 15September 26
90% (likely)May 1October 8
Frost-free season (32°F, 50% chance)
134 days
Hard frost (28°F), last in spring, 50% chance after
May 4
Hard frost (28°F), first in fall, 50% chance before
October 6

The last 15 years (2006–2020 normals)

Typical last frost May 15 (same as the 30-year normal), typical first fall frost September 30 (4 days later). Frost-free season 135 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 Argyle: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 28, 20% May 24, 30% May 21, 40% May 17, 50% May 15, 60% May 12, 70% May 9, 80% May 5, 90% May 1.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 28May 15May 1Fall at Argyle: chance of a frost before this dateFall, chance of a frost before the date: 10% September 13, 20% September 18, 30% September 21, 40% September 24, 50% September 26, 60% September 29, 70% October 1, 80% October 3, 90% October 8.Fall: first frostChance of a frost before this date10%50%90%Sep 1Oct 1Sep 13Sep 26Oct 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.

What these dates mean

May 28 is the cautious spring date in Argyle; with only a 10 % chance of a light frost later, it marks the point when a gardener can reasonably set out tender crops. The early spring gamble is May 1, which carries a 90 % chance of a frost later, while the median point is the 50 % date of May 15, where the odds of a light frost are equal.

In fall the cautious date is September 13, where there is only a 10 % chance that a light frost has arrived earlier, making it the appropriate moment to finish harvesting tender crops. The median point is September 26, the 50 % date, and the late-season gamble is October 8, which carries a 90 % chance of a frost earlier.

Hard frost at 28 °F can cause far more damage to plants than a light frost at 32 °F, so the median hard-frost dates of May 4 and October 6 are useful reference points.

How to read the probabilities

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

  • Spring: "10% after May 28" 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 13" 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 Argyle, MNNumbered nearest stations: 1 — near Grand Forks, ND — 31 mi; 2 — Grand Forks (Airport), ND — 32 mi; 3 — near Crookston, MN — 37 mi; 4 — Red Lake Falls, MN — 40 mi; 5 — Pembina, ND — 48 mi.MNND25 mi · 40 km1. near Grand Forks, ND — 31 mi12. Grand Forks (Airport), ND — 32 mi23. near Crookston, MN — 37 mi34. Red Lake Falls, MN — 40 mi45. Pembina, ND — 48 mi5
  1. near Grand Forks, ND 31 mi (50 km)
  2. Grand Forks (Airport), ND 32 mi (51 km)
  3. near Crookston, MN 37 mi (59 km)
  4. Red Lake Falls, MN 40 mi (64 km)
  5. Pembina, ND 48 mi (77 km)

Sources

* Hardiness zone 4a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 48.3311, -96.8253.