U.S. Frost Dates by Weather Station

NOAA station USW00024219 · Washington

Frost Dates near Dallesport, WA

NOAA weather station The Dalles Municipal Airport (USW00024219), Washington · elevation 235 ft (72 m) · hardiness zone 8a*

Dallesport is the nearest town to the station (0.7 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 April 28only 1 spring in 10 still has a frost later
  • Typical last frostApril 1150% chance of a frost after it
  • Typical first fall frostOctober 2650% chance of a frost before it
  • Frost-free season197 daystypical year, 32°F
  • Hardiness zone8acalculated*

The year at a glance

Frost season near Dallesport, WASpring: a frost after March 24 in 9 years out of 10, after April 11 in half of the years, after April 28 in 1 year out of 10. Fall: the first frost comes before October 9 in 1 year out of 10, before October 26 in half of the years, before November 10 in 9 years out of 10. Typical frost-free season: 197 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 11First frost ~Oct 26Frost season near Dallesport, WASpring: a frost after March 24 in 9 years out of 10, after April 11 in half of the years, after April 28 in 1 year out of 10. Fall: the first frost comes before October 9 in 1 year out of 10, before October 26 in half of the years, before November 10 in 9 years out of 10. Typical frost-free season: 197 days.JFMAMJJASONDLast frost ~Apr 11First frost ~Oct 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)April 28October 9
50% (typical)April 11October 26
90% (likely)March 24November 10
Frost-free season (32°F, 50% chance)
197 days
Hard frost (28°F), last in spring, 50% chance after
March 16
Hard frost (28°F), first in fall, 50% chance before
November 7

The last 15 years (2006–2020 normals)

Typical last frost April 11 (same as the 30-year normal), typical first fall frost October 25 (1 day earlier). Frost-free season 194 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 Dallesport: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 28, 20% April 24, 30% April 19, 40% April 15, 50% April 11, 60% April 7, 70% April 3, 80% March 30, 90% March 24. Observed last spring frost in recent years: 2021 April 20, 2022 April 6, 2023 April 20, 2024 April 18, 2025 April 14, 2026 March 27.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 28Apr 11Mar 242021: April 202022: April 62023: April 202024: April 182025: April 142026: March 27Fall near Dallesport: chance of a frost before this dateFall, chance of a frost before the date: 10% October 9, 20% October 15, 30% October 19, 40% October 22, 50% October 26, 60% October 29, 70% November 1, 80% November 4, 90% November 10. Observed first fall frost in recent years: 2021 November 17, 2022 November 3, 2023 October 27, 2024 October 25, 2025 November 19.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 9Oct 26Nov 102021: November 172022: November 32023: October 272024: October 252025: November 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
2021April 20November 17
2022April 6November 3
2023April 20October 27
2024April 18October 25
2025April 14November 19
2026March 27season not over yet

What these dates mean

April 28 is the cautious spring date for the Dallesport area; with only a 10 % chance of a light frost later, it marks the earliest point a gardener can confidently set out tender crops. The median spring date, April 11, carries a 50 % chance of a light frost later, while the gamble date of March 24 carries a 90 % chance of frost later.

In fall, the cautious date is October 9, when there is only a 10 % chance that a light frost has arrived, allowing growers to finish harvesting tender crops. The median fall date, October 26, reflects a 50 % chance of a light frost earlier, and the gamble date of November 10 carries a 90 % chance of frost earlier. The hard-frost 50 % dates are March 16 in spring and November 7 in fall; a hard frost can damage plant tissue that survives a light frost, making it a more critical threshold.

How to read the probabilities

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

  • Spring: "10% after April 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 October 9" 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 Dallesport, WANumbered nearest stations: 1 — Moro, OR — 23 mi; 2 — Government Camp, OR — 36 mi; 3 — near Cascade Locks, OR — 38 mi; 4 — near Carson, WA — 43 mi; 5 — near Sandy, OR — 49 mi.ORWA25 mi · 40 km1. Moro, OR — 23 mi12. Government Camp, OR — 36 mi23. near Cascade Locks, OR — 38 mi34. near Carson, WA — 43 mi45. near Sandy, OR — 49 mi5
  1. Moro, OR 23 mi (38 km)
  2. Government Camp, OR 36 mi (57 km)
  3. near Cascade Locks, OR 38 mi (61 km)
  4. near Carson, WA 43 mi (68 km)
  5. near Sandy, OR 49 mi (79 km)

Sources

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

Station coordinates: 45.6194, -121.1661.