U.S. Frost Dates by Weather Station

NOAA station USC00459074 · Washington

Frost Dates for Wenatchee, WA

NOAA weather station Wenatchee (USC00459074), Washington · elevation 626 ft (191 m) · hardiness zone 7b*

  • Lower-risk planting dateafter April 19only 1 spring in 10 still has a frost later
  • Typical last frostApril 450% chance of a frost after it
  • Typical first fall frostOctober 2850% chance of a frost before it
  • Frost-free season208 daystypical year, 32°F
  • Hardiness zone7bcalculated*

The year at a glance

Frost season at Wenatchee, WASpring: a frost after March 17 in 9 years out of 10, after April 4 in half of the years, after April 19 in 1 year out of 10. Fall: the first frost comes before October 17 in 1 year out of 10, before October 28 in half of the years, before November 11 in 9 years out of 10. Typical frost-free season: 208 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 4First frost ~Oct 28Frost season at Wenatchee, WASpring: a frost after March 17 in 9 years out of 10, after April 4 in half of the years, after April 19 in 1 year out of 10. Fall: the first frost comes before October 17 in 1 year out of 10, before October 28 in half of the years, before November 11 in 9 years out of 10. Typical frost-free season: 208 days.JFMAMJJASONDLast frost ~Apr 4First frost ~Oct 28
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 28 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 19October 17
50% (typical)April 4October 28
90% (likely)March 17November 11
Frost-free season (32°F, 50% chance)
208 days
Hard frost (28°F), last in spring, 50% chance after
March 13
Hard frost (28°F), first in fall, 50% chance before
November 10

The last 15 years (2006–2020 normals)

Typical last frost April 2 (2 days earlier than the 30-year normal), typical first fall frost October 29 (1 day later). Frost-free season 208 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 Wenatchee: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 19, 20% April 14, 30% April 10, 40% April 7, 50% April 4, 60% April 1, 70% March 30, 80% March 25, 90% March 17. Observed last spring frost in recent years: 2021 April 12, 2022 April 16, 2023 April 5, 2024 May 1, 2025 March 20.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 19Apr 4Mar 172021: April 122022: April 162023: April 52024: May 12025: March 20Fall at Wenatchee: chance of a frost before this dateFall, chance of a frost before the date: 10% October 17, 20% October 20, 30% October 23, 40% October 26, 50% October 28, 60% October 31, 70% November 2, 80% November 6, 90% November 11. Observed first fall frost in recent years: 2021 October 30, 2022 November 3, 2023 October 28, 2024 November 7.Fall: first frostChance of a frost before this date10%50%90%Nov 1Oct 17Oct 28Nov 112021: October 302022: November 32023: October 282024: November 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
2021April 12October 30
2022April 16November 3
2023April 5October 28
2024May 1November 7
2025March 20incomplete record
2026incomplete recordseason not over yet

What these dates mean

Setting tender crops on March 17 carries a 90% chance of a light frost later, making it a gamble for gardeners in Wenatchee.

The 50% date is April 4 for spring and October 28 for fall; at each of these dates there is a 50% chance of a light frost later (spring) or earlier (fall). A cautious plan would wait until April 19 to set out tender crops in spring and finish harvesting them by October 17 in fall, each carrying only a 10% chance of a light frost.

A hard frost at 28 °F, recorded by the median dates March 13 and November 10, can damage plants more severely than a light frost at 32 °F, so it is a higher risk 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 19" 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 17" 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 Wenatchee, WANumbered nearest stations: 1 — Wenatchee (Pangborn Airport), WA — 6 mi; 2 — near Entiat, WA — 19 mi; 3 — Plain, WA — 29 mi; 4 — Chelan, WA — 32 mi; 5 — Ephrata, WA — 38 mi.WA25 mi · 40 km1. Wenatchee (Pangborn Airport), WA — 6 mi12. near Entiat, WA — 19 mi23. Plain, WA — 29 mi34. Chelan, WA — 32 mi45. Ephrata, WA — 38 mi5
  1. Wenatchee (Pangborn Airport), WA 6 mi (9 km)
  2. near Entiat, WA 19 mi (30 km)
  3. Plain, WA 29 mi (47 km)
  4. Chelan, WA 32 mi (51 km)
  5. Ephrata, WA 38 mi (61 km)

Sources

* Hardiness zone 7b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 47.4289, -120.31.