U.S. Frost Dates by Weather Station

NOAA station USC00452563 · Washington

Frost Dates near Entiat, WA

NOAA weather station Entiat Fish Hatchery (USC00452563), Washington · elevation 1027 ft (313 m) · hardiness zone 7a*

Entiat is the nearest town to the station (5.5 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 May 2only 1 spring in 10 still has a frost later
  • Typical last frostApril 550% chance of a frost after it
  • Typical first fall frostOctober 2450% chance of a frost before it
  • Frost-free season200 daystypical year, 32°F
  • Hardiness zone7acalculated*

The year at a glance

Frost season near Entiat, WASpring: a frost after March 17 in 9 years out of 10, after April 5 in half of the years, after May 2 in 1 year out of 10. Fall: the first frost comes before September 29 in 1 year out of 10, before October 24 in half of the years, before November 10 in 9 years out of 10. Typical frost-free season: 200 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 5First frost ~Oct 24Frost season near Entiat, WASpring: a frost after March 17 in 9 years out of 10, after April 5 in half of the years, after May 2 in 1 year out of 10. Fall: the first frost comes before September 29 in 1 year out of 10, before October 24 in half of the years, before November 10 in 9 years out of 10. Typical frost-free season: 200 days.JFMAMJJASONDLast frost ~Apr 5First 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 26 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 2September 29
50% (typical)April 5October 24
90% (likely)March 17November 10
Frost-free season (32°F, 50% chance)
200 days
Hard frost (28°F), last in spring, 50% chance after
March 13
Hard frost (28°F), first in fall, 50% chance before
November 7

The last 15 years (2006–2020 normals)

Typical last frost April 7 (2 days later than the 30-year normal), typical first fall frost October 26 (2 days later). Frost-free season 198 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 Entiat: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 2, 20% April 21, 30% April 13, 40% April 8, 50% April 5, 60% April 1, 70% March 30, 80% March 25, 90% March 17. Observed last spring frost in recent years: 2021 April 15, 2022 April 21, 2023 April 20, 2024 April 9, 2025 April 10, 2026 April 16.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 2Apr 5Mar 172021: April 152022: April 212023: April 202024: April 92025: April 102026: April 16Fall near Entiat: chance of a frost before this dateFall, chance of a frost before the date: 10% September 29, 20% October 10, 30% October 17, 40% October 21, 50% October 24, 60% October 27, 70% October 31, 80% November 4, 90% November 10. Observed first fall frost in recent years: 2021 October 12, 2022 November 3, 2023 October 28, 2024 October 25, 2025 October 15.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 29Oct 24Nov 102021: October 122022: November 32023: October 282024: October 252025: October 15
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 15October 12
2022April 21November 3
2023April 20October 28
2024April 9October 25
2025April 10October 15
2026April 16season not over yet

What these dates mean

The cautious fall date in the Entiat area for finishing the harvest is September 29, when there is only a 10 % chance that a light frost has arrived.

The 50 % light-frost dates—April 5 in spring and October 24 in fall—mark the points at which a gardener faces an even chance of a frost occurring later (spring) or earlier (fall). For a low-risk plan, the spring cautious date is May 2, the day with a 10 % chance of frost later, while the fall cautious date is September 29, the day with a 10 % chance of frost earlier.

Hard-frost dates (28 °F) are March 13 and November 7, and a hard frost matters more than a light frost because temperatures at 28 °F can freeze plant tissues that survive the milder 32 °F chill.

How to read the probabilities

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

  • Spring: "10% after May 2" 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 29" 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 Entiat, WANumbered nearest stations: 1 — Plain, WA — 16 mi; 2 — Chelan, WA — 18 mi; 3 — Wenatchee, WA — 19 mi; 4 — Wenatchee (Pangborn Airport), WA — 22 mi; 5 — near Bridgeport, WA — 37 mi.25 mi · 40 km1. Plain, WA — 16 mi12. Chelan, WA — 18 mi23. Wenatchee, WA — 19 mi34. Wenatchee (Pangborn Airport), WA — 22 mi45. near Bridgeport, WA — 37 mi5
  1. Plain, WA 16 mi (26 km)
  2. Chelan, WA 18 mi (28 km)
  3. Wenatchee, WA 19 mi (30 km)
  4. Wenatchee (Pangborn Airport), WA 22 mi (35 km)
  5. near Bridgeport, WA 37 mi (60 km)

Sources

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

Station coordinates: 47.6983, -120.3228.