U.S. Frost Dates by Weather Station

NOAA station USC00426869 · Utah

Frost Dates near Ogden, UT

NOAA weather station Pineview Dam (USC00426869), Utah · elevation 4940 ft (1506 m) · hardiness zone 6a*

Ogden is the nearest town to the station (7.5 mi away) in GeoNames (CC BY 4.0). The dates below are measured at the station, not in the town itself.

  • Lower-risk planting dateafter June 8only 1 spring in 10 still has a frost later
  • Typical last frostMay 2250% chance of a frost after it
  • Typical first fall frostSeptember 2650% chance of a frost before it
  • Frost-free season125 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season near Ogden, UTSpring: a frost after May 7 in 9 years out of 10, after May 22 in half of the years, after June 8 in 1 year out of 10. Fall: the first frost comes before September 11 in 1 year out of 10, before September 26 in half of the years, before October 9 in 9 years out of 10. Typical frost-free season: 125 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 22First frost ~Sep 26Frost season near Ogden, UTSpring: a frost after May 7 in 9 years out of 10, after May 22 in half of the years, after June 8 in 1 year out of 10. Fall: the first frost comes before September 11 in 1 year out of 10, before September 26 in half of the years, before October 9 in 9 years out of 10. Typical frost-free season: 125 days.JFMAMJJASONDLast frost ~May 22First 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 27 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)June 8September 11
50% (typical)May 22September 26
90% (likely)May 7October 9
Frost-free season (32°F, 50% chance)
125 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 18 (4 days earlier than the 30-year normal), typical first fall frost October 2 (6 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 near Ogden: chance of a frost after this dateSpring, chance of a frost after the date: 10% June 8, 20% June 2, 30% May 30, 40% May 26, 50% May 22, 60% May 18, 70% May 15, 80% May 12, 90% May 7. Observed last spring frost in recent years: 2021 May 22, 2022 May 24, 2023 May 7, 2024 June 19, 2025 May 19, 2026 May 21.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1Jun 8May 22May 72021: May 222022: May 242023: May 72024: June 192025: May 192026: May 21Fall near Ogden: chance of a frost before this dateFall, chance of a frost before the date: 10% September 11, 20% September 16, 30% September 20, 40% September 23, 50% September 26, 60% September 29, 70% October 1, 80% October 5, 90% October 9. Observed first fall frost in recent years: 2021 September 21, 2022 October 14, 2023 October 16, 2024 October 25, 2025 October 7.Fall: first frostChance of a frost before this date10%50%90%Sep 1Oct 1Nov 1Sep 11Sep 26Oct 92021: September 212022: October 142023: October 162024: October 252025: October 7
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 22September 21
2022May 24October 14
2023May 7October 16
2024June 19October 25
2025May 19October 7
2026May 21season not over yet

What these dates mean

June 8 is the cautious spring light-frost date for the Ogden area; with only a 10 % chance of a frost later, a gardener can plan to set out tender crops on that day. The median 50 % date of May 22 marks the point at which a frost is as likely as not, giving a statistical reference but not a frost-free guarantee.

In the fall the cautious light-frost date is September 11, when there is just a 10 % chance that a frost has already arrived, allowing a grower to finish harvesting tender crops. The median 50 % date of September 26 provides a balanced reference for later decisions. The hard-frost 50 % dates are May 4 in spring and October 6 in fall; a hard frost can damage or kill plants that survive a light frost, making it a more severe threat.

How to read the probabilities

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

  • Spring: "10% after June 8" 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 11" 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 Ogden, UTNumbered nearest stations: 1 — Brigham City, UT — 21 mi; 2 — near Bountiful, UT — 25 mi; 3 — near Coalville, UT — 29 mi; 4 — Logan Radio Kvnu, UT — 33 mi; 5 — near Logan, UT — 34 mi.WYID25 mi · 40 km1. Brigham City, UT — 21 mi12. near Bountiful, UT — 25 mi23. near Coalville, UT — 29 mi34. Logan Radio Kvnu, UT — 33 mi45. near Logan, UT — 34 mi5
  1. Brigham City, UT 21 mi (34 km)
  2. near Bountiful, UT 25 mi (41 km)
  3. near Coalville, UT 29 mi (47 km)
  4. Logan Radio Kvnu, UT 33 mi (53 km)
  5. near Logan, UT 34 mi (54 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: 41.2578, -111.8378.