U.S. Frost Dates by Weather Station

NOAA station USC00351643 · Oregon

Frost Dates for Clatskanie, OR

NOAA weather station Clatskanie (USC00351643), Oregon · elevation 22 ft (7 m) · hardiness zone 8b*

  • Lower-risk planting dateafter May 9only 1 spring in 10 still has a frost later
  • Typical last frostApril 2450% 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 Clatskanie, ORSpring: a frost after March 31 in 9 years out of 10, after April 24 in half of the years, after May 9 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 12 in 9 years out of 10. Typical frost-free season: 184 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 24First frost ~Oct 24Frost season at Clatskanie, ORSpring: a frost after March 31 in 9 years out of 10, after April 24 in half of the years, after May 9 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 12 in 9 years out of 10. Typical frost-free season: 184 days.JFMAMJJASONDLast frost ~Apr 24First 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 30 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 9October 5
50% (typical)April 24October 24
90% (likely)March 31November 12
Frost-free season (32°F, 50% chance)
184 days
Hard frost (28°F), last in spring, 50% chance after
March 25
Hard frost (28°F), first in fall, 50% chance before
November 9

The last 15 years (2006–2020 normals)

Typical last frost April 23 (1 day earlier than the 30-year normal), typical first fall frost October 22 (2 days earlier). Frost-free season 185 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 Clatskanie: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 9, 20% May 4, 30% May 1, 40% April 28, 50% April 24, 60% April 19, 70% April 14, 80% April 8, 90% March 31. Observed last spring frost in recent years: 2021 April 14, 2022 May 12, 2023 April 14, 2024 April 22.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 9Apr 24Mar 312021: April 142022: May 122023: April 142024: April 22Fall at Clatskanie: chance of a frost before this dateFall, chance of a frost before the date: 10% October 5, 20% October 9, 30% October 15, 40% October 20, 50% October 24, 60% October 27, 70% November 1, 80% November 6, 90% November 12. Observed first fall frost in recent years: 2021 October 12, 2022 November 9, 2023 October 28, 2024 October 24.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 5Oct 24Nov 122021: October 122022: November 92023: October 282024: October 24
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 14October 12
2022May 12November 9
2023April 14October 28
2024April 22October 24
2025incomplete recordno data
2026no dataseason not over yet

What these dates mean

The 184 days between the 50% dates in Clatskanie, April 24 and October 24, define the span in which a light frost (32 °F) is statistically less likely than not. For a gardener this median window indicates when the odds of a frost are below 50 % on either side, offering a practical reference for timing activities that are sensitive to light frost.

To minimize risk, the cautious spring date for setting out tender crops is May 9, when there is only a 10 % chance of a later frost, while the cautious fall date to finish harvesting tender crops is October 5, when there is only a 10 % chance that a frost has already arrived. A hard frost, recorded at 28 °F, is more consequential than a light frost because the lower temperature can cause more severe damage to plant tissue.

How to read the probabilities

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

  • Spring: "10% after May 9" 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 Clatskanie, ORNumbered nearest stations: 1 — Longview, WA — 14 mi; 2 — near Vernonia, OR — 17 mi; 3 — Astoria, OR — 33 mi; 4 — Vancouver, WA — 40 mi; 5 — Battle Ground, WA — 40 mi.ORWA25 mi · 40 km1. Longview, WA — 14 mi12. near Vernonia, OR — 17 mi23. Astoria, OR — 33 mi34. Vancouver, WA — 40 mi45. Battle Ground, WA — 40 mi5
  1. Longview, WA 14 mi (23 km)
  2. near Vernonia, OR 17 mi (27 km)
  3. Astoria, OR 33 mi (52 km)
  4. Vancouver, WA 40 mi (64 km)
  5. Battle Ground, WA 40 mi (64 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: 46.1081, -123.2058.