U.S. Frost Dates by Weather Station

NOAA station USW00094290 · Washington

Frost Dates near Kirkland, WA

NOAA weather station Seattle Sand Point WSFO (USW00094290), Washington · elevation 60 ft (18 m) · hardiness zone 9a*

Kirkland is the nearest town to the station (2.2 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 March 29only 1 spring in 10 still has a frost later
  • Typical last frostMarch 850% chance of a frost after it
  • Typical first fall frostNovember 2350% chance of a frost before it
  • Frost-free season259 daystypical year, 32°F
  • Hardiness zone9acalculated*

The year at a glance

Frost season near Kirkland, WASpring: a frost after February 13 in 9 years out of 10, after March 8 in half of the years, after March 29 in 1 year out of 10. Fall: the first frost comes before November 4 in 1 year out of 10, before November 23 in half of the years, before December 16 in 9 years out of 10. Typical frost-free season: 259 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 8First frost ~Nov 23Frost season near Kirkland, WASpring: a frost after February 13 in 9 years out of 10, after March 8 in half of the years, after March 29 in 1 year out of 10. Fall: the first frost comes before November 4 in 1 year out of 10, before November 23 in half of the years, before December 16 in 9 years out of 10. Typical frost-free season: 259 days.JFMAMJJASONDLast frost ~Mar 8First frost ~Nov 23
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.Today

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)March 29November 4
50% (typical)March 8November 23
90% (likely)February 13December 16
Frost-free season (32°F, 50% chance)
259 days
Hard frost (28°F), last in spring, 50% chance after
February 11
Hard frost (28°F), first in fall, 50% chance before
December 11

The last 15 years (2006–2020 normals)

Typical last frost March 9 (1 day later than the 30-year normal), typical first fall frost November 24 (1 day later). Frost-free season 255 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 Kirkland: chance of a frost after this dateSpring, chance of a frost after the date: 10% March 29, 20% March 21, 30% March 16, 40% March 11, 50% March 8, 60% March 3, 70% February 27, 80% February 23, 90% February 13. Observed last spring frost in recent years: 2021 March 30, 2022 March 10, 2024 March 7, 2025 February 13, 2026 March 13.Spring: last frostChance of a frost after this date10%50%90%Feb 1Mar 1Apr 1Mar 29Mar 8Feb 132021: March 302022: March 102024: March 72025: February 132026: March 13Fall near Kirkland: chance of a frost before this dateFall, chance of a frost before the date: 10% November 4, 20% November 10, 30% November 15, 40% November 19, 50% November 23, 60% November 27, 70% December 1, 80% December 6, 90% December 16. Observed first fall frost in recent years: 2021 December 26, 2022 November 9, 2023 October 28, 2024 December 3, 2025 December 31.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Jan 1Nov 4Nov 23Dec 162021: December 262022: November 92023: October 282024: December 32025: December 31
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
2021March 30December 26
2022March 10November 9
2023incomplete recordOctober 28
2024March 7December 3
2025February 13December 31
2026March 13season not over yet

What these dates mean

259 days separate the 50% light-frost dates of March 8 and November 23, framing the central period during which most garden tasks can be scheduled in the Kirkland area.

The 50% date of March 8 carries a 50% chance of a frost later than that day, while the 50% date of November 23 carries a 50% chance of a frost earlier than that day. For a cautious approach to tender crops, gardeners use the late spring light-frost date of March 29, which has only a 10% chance of a later frost, and the early fall light-frost date of November 4, which has only a 10% chance of an earlier frost. The early-spring date of February 13 and the late-fall date of December 16 each carry a 90% chance of frost and represent gambles.

Hard frost at 28 °F is more damaging than a light frost at 32 °F, making the median hard-frost dates of February 11 and December 11 especially important for plant survival.

How to read the probabilities

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

  • Spring: "10% after March 29" 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 November 4" 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 Kirkland, WANumbered nearest stations: 1 — Seattle (Seattle-Tacoma Airport), WA — 17 mi; 2 — Kent, WA — 19 mi; 3 — Everett, WA — 20 mi; 4 — Startup, WA — 28 mi; 5 — near Wilderness Rim, WA — 30 mi.WA25 mi · 40 km1. Seattle (Seattle-Tacoma Airport), WA — 17 mi12. Kent, WA — 19 mi23. Everett, WA — 20 mi34. Startup, WA — 28 mi45. near Wilderness Rim, WA — 30 mi5
  1. Seattle (Seattle-Tacoma Airport), WA 17 mi (27 km)
  2. Kent, WA 19 mi (30 km)
  3. Everett, WA 20 mi (32 km)
  4. Startup, WA 28 mi (45 km)
  5. near Wilderness Rim, WA 30 mi (48 km)

Sources

* Hardiness zone 9a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 47.6872, -122.2553.