U.S. Frost Dates by Weather Station

NOAA station USC00425182 · Utah

Frost Dates for Logan Radio Kvnu, UT

NOAA weather station Logan Radio Kvnu (USC00425182), Utah · elevation 4475 ft (1364 m) · hardiness zone 6a*

  • Lower-risk planting dateafter June 2only 1 spring in 10 still has a frost later
  • Typical last frostMay 850% chance of a frost after it
  • Typical first fall frostOctober 250% chance of a frost before it
  • Frost-free season145 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Logan Radio Kvnu, UTSpring: a frost after April 25 in 9 years out of 10, after May 8 in half of the years, after June 2 in 1 year out of 10. Fall: the first frost comes before September 18 in 1 year out of 10, before October 2 in half of the years, before October 15 in 9 years out of 10. Typical frost-free season: 145 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 8First frost ~Oct 2Frost season at Logan Radio Kvnu, UTSpring: a frost after April 25 in 9 years out of 10, after May 8 in half of the years, after June 2 in 1 year out of 10. Fall: the first frost comes before September 18 in 1 year out of 10, before October 2 in half of the years, before October 15 in 9 years out of 10. Typical frost-free season: 145 days.JFMAMJJASONDLast frost ~May 8First frost ~Oct 2
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)June 2September 18
50% (typical)May 8October 2
90% (likely)April 25October 15
Frost-free season (32°F, 50% chance)
145 days
Hard frost (28°F), last in spring, 50% chance after
April 23
Hard frost (28°F), first in fall, 50% chance before
October 14

The last 15 years (2006–2020 normals)

Typical last frost May 10 (2 days later than the 30-year normal), typical first fall frost October 4 (2 days later). Frost-free season 146 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 Logan Radio Kvnu: chance of a frost after this dateSpring, chance of a frost after the date: 10% June 2, 20% May 21, 30% May 16, 40% May 12, 50% May 8, 60% May 6, 70% May 3, 80% April 30, 90% April 25. Observed last spring frost in recent years: 2021 May 11, 2022 May 23, 2023 April 26, 2024 June 18, 2025 April 20, 2026 May 19.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1Jun 2May 8Apr 252021: May 112022: May 232023: April 262024: June 182025: April 202026: May 19Fall at Logan Radio Kvnu: chance of a frost before this dateFall, chance of a frost before the date: 10% September 18, 20% September 22, 30% September 26, 40% September 30, 50% October 2, 60% October 5, 70% October 7, 80% October 11, 90% October 15. Observed first fall frost in recent years: 2021 September 30, 2022 October 14, 2023 September 23, 2024 October 19, 2025 October 19.Fall: first frostChance of a frost before this date10%50%90%Oct 1Sep 18Oct 2Oct 152021: September 302022: October 142023: September 232024: October 192025: October 19
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 11September 30
2022May 23October 14
2023April 26September 23
2024June 18October 19
2025April 20October 19
2026May 19season not over yet

What these dates mean

September 18 is the cautious fall date in Logan Radio Kvnu for finishing the harvest, because there is only a 10 % chance that a light frost has arrived by then.

The cautious spring date for setting out tender crops is June 2, when the chance of a light frost later than that date is just 10 %. The 50 % spring date, May 8, marks the point at which a light frost is equally likely to occur later; similarly, the 50 % fall date, October 2, indicates an even chance of a frost earlier than that day.

The median hard-frost dates are April 23 in spring and October 14 in fall. A hard frost at 28 °F can damage plant tissue that would survive a light frost at 32 °F, making it a more critical threshold for tender crops.

How to read the probabilities

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

  • Spring: "10% after June 2" 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 18" 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 Logan Radio Kvnu, UTNumbered nearest stations: 1 — near Logan, UT — 3 mi; 2 — Richmond, UT — 12 mi; 3 — near Garland, UT — 12 mi; 4 — Brigham City, UT — 17 mi; 5 — Preston, ID — 25 mi.UTIDWY25 mi · 40 km1. near Logan, UT — 3 mi12. Richmond, UT — 12 mi23. near Garland, UT — 12 mi34. Brigham City, UT — 17 mi45. Preston, ID — 25 mi5
  1. near Logan, UT 3 mi (5 km)
  2. Richmond, UT 12 mi (19 km)
  3. near Garland, UT 12 mi (20 km)
  4. Brigham City, UT 17 mi (28 km)
  5. Preston, ID 25 mi (40 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: 41.735, -111.8564.