U.S. Frost Dates by Weather Station

NOAA station USC00354606 · Oregon

Frost Dates for Lacomb, OR

NOAA weather station Lacomb 3 NNE (USC00354606), Oregon · elevation 520 ft (159 m) · hardiness zone 8b*

  • Lower-risk planting dateafter May 11only 1 spring in 10 still has a frost later
  • Typical last frostApril 2650% chance of a frost after it
  • Typical first fall frostOctober 2450% chance of a frost before it
  • Frost-free season184 daystypical year, 32°F
  • Hardiness zone8bcalculated*

The year at a glance

Frost season at Lacomb, ORSpring: a frost after April 4 in 9 years out of 10, after April 26 in half of the years, after May 11 in 1 year out of 10. Fall: the first frost comes before October 5 in 1 year out of 10, before October 24 in half of the years, before November 14 in 9 years out of 10. Typical frost-free season: 184 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 26First frost ~Oct 24Frost season at Lacomb, ORSpring: a frost after April 4 in 9 years out of 10, after April 26 in half of the years, after May 11 in 1 year out of 10. Fall: the first frost comes before October 5 in 1 year out of 10, before October 24 in half of the years, before November 14 in 9 years out of 10. Typical frost-free season: 184 days.JFMAMJJASONDLast frost ~Apr 26First frost ~Oct 24
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)May 11October 5
50% (typical)April 26October 24
90% (likely)April 4November 14
Frost-free season (32°F, 50% chance)
184 days
Hard frost (28°F), last in spring, 50% chance after
March 24
Hard frost (28°F), first in fall, 50% chance before
November 12

The last 15 years (2006–2020 normals)

Typical last frost April 29 (3 days later than the 30-year normal), typical first fall frost October 21 (3 days earlier). Frost-free season 177 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 Lacomb: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 11, 20% May 5, 30% May 1, 40% April 29, 50% April 26, 60% April 22, 70% April 17, 80% April 11, 90% April 4. Observed last spring frost in recent years: 2021 April 16, 2022 April 23, 2023 April 5, 2024 April 23, 2025 May 4, 2026 April 17.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 11Apr 26Apr 42021: April 162022: April 232023: April 52024: April 232025: May 42026: April 17Fall at Lacomb: chance of a frost before this dateFall, chance of a frost before the date: 10% October 5, 20% October 12, 30% October 17, 40% October 20, 50% October 24, 60% October 28, 70% November 1, 80% November 7, 90% November 14. Observed first fall frost in recent years: 2021 October 12, 2022 November 7, 2023 October 27, 2024 October 24, 2025 October 14.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 5Oct 24Nov 142021: October 122022: November 72023: October 272024: October 242025: October 14
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
2021April 16October 12
2022April 23November 7
2023April 5October 27
2024April 23October 24
2025May 4October 14
2026April 17season not over yet

What these dates mean

October 5 is the cautious fall date for finishing the harvest in Lacomb, carrying only a 10 % chance that a light frost has arrived earlier. In spring the cautious date for setting out tender crops is May 11, which has a 10 % chance of a frost later.

The 50 % light-frost dates, April 26 in spring and October 24 in fall, mark the point where the odds of a frost later (spring) or earlier (fall) are equal. A gardener using a cautious plan would wait until the May 11 date to plant tender crops and would aim to conclude tender harvest by the October 5 date.

Hard frost at 28 °F can damage plants that survive a light frost at 32 °F, so it is more critical to monitor. The median hard-frost dates are March 24 and November 12, each representing a 50 % chance of a hard frost later in spring or earlier in fall.

How to read the probabilities

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

  • Spring: "10% after May 11" 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 October 5" 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 Lacomb, ORNumbered nearest stations: 1 — Stayton, OR — 12 mi; 2 — near Sweet Home, OR — 15 mi; 3 — near Corvallis, OR — 23 mi; 4 — Silverton, OR — 26 mi; 5 — Dallas, OR — 36 mi.25 mi · 40 km1. Stayton, OR — 12 mi12. near Sweet Home, OR — 15 mi23. near Corvallis, OR — 23 mi34. Silverton, OR — 26 mi45. Dallas, OR — 36 mi5
  1. Stayton, OR 12 mi (20 km)
  2. near Sweet Home, OR 15 mi (24 km)
  3. near Corvallis, OR 23 mi (37 km)
  4. Silverton, OR 26 mi (43 km)
  5. Dallas, OR 36 mi (58 km)

Sources

* Hardiness zone 8b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 44.625, -122.7192.