FrostList

When to Winterize Your RV in Burien, WA

ON TRACK152 days until first 28°F freezeDec 10

In a typical year, winterize your RV in Burien by November 30. The median first 28°F hard freeze at Burien's NOAA station is December 10 (1991–2020 normals); one year in ten it arrives as early as November 17. Plan for the early end: the one-in-ten date lands about 23 days before the median.

OUTLOOK

Typical first first 28°F freeze near Dec 10; local deadline about Nov 30. The live 10-day outlook loads here.

Local freeze dates for Burien

ThresholdEarly (1-in-10)MedianLate (9-in-10)
32°F (light freeze)Nov 6Nov 23Dec 15
28°F (hard freeze)Nov 17Dec 10Jan 16
24°F (severe)Nov 26Dec 17Feb 1

NOAA station: Seattle Tacoma Intl AP · 2.4 mi away · 370 ft elevation.

The reference station for Burien is Seattle Tacoma Intl AP (2.4 mi, 370 ft). First freeze there: 32°F by Nov 23, 28°F by Dec 10, 24°F by Dec 17. The 28°F freeze has come as early as Nov 17 and as late as Jan 16, a 60-day spread. Spring's last 32°F freeze clears around Mar 2. Snowfall averages 6 inches a year, first reaching an inch near December.

Expect the first frost near Nov 23 in Burien and the first hard freeze by about Dec 10. That first freezing night has ranged from Nov 6 to Dec 15, roughly a 39-day spread. On the spring side, the last 32°F freeze clears around Mar 2 and as late as Mar 23 — the green light for reopening water and de-winterizing. Only about 6 inches of snow falls in a typical year, so cold protection outranks snow removal.

Your rv checklist

  1. Drain the fresh, gray, and black tanks, then drain the water heater only after it has cooled and lost pressure.
  2. Bypass the water heater so you do not waste six gallons of antifreeze filling the tank.
  3. Blow out the lines with a compressor at about 30–40 psi, then pump non-toxic RV antifreeze through every faucet until it runs pink.
    Helpful gear: RV antifreeze (6-pack) — Recommended pick
  4. Use a water-pump converter kit to draw antifreeze straight from the jug through the plumbing.
    Helpful gear: Water pump converter kit — Recommended pick
  5. Pour a cup of antifreeze into each drain trap and the toilet to protect the seals.
  6. Fit a blow-out plug at the city-water inlet so you can clear that line too.
    Helpful gear: Blow-out plug — Recommended pick
  7. Remove batteries or put them on a maintainer, and store them off a cold concrete floor.
  8. Cover roof vents, close the propane, and set out traps or deterrents so mice do not move in.

What to have on hand

RV antifreeze (6-pack)
Non-toxic pink fluid for the fresh-water plumbing and traps.
Recommended pick
Water pump converter kit
Siphon kit that draws antifreeze straight through the pump.
Recommended pick
Blow-out plug
Adapter that lets a compressor clear the lines before antifreeze.
Recommended pick
Heated fresh-water hose
For anyone staying hooked up through a cold snap.
Recommended pick

What this means locally

Burien freezes later than Renton (Dec 6) and later than Kent (Nov 24) — a reminder that even nearby towns differ by days. Statewide, Washington prep dates run Oct 6 through Dec 1, which is why Burien gets its own number rather than a Washington-wide average. The same freeze also decides when to shut down your sprinklers and winterize a boat.

Other winter jobs in Burien

Every task below is dated to Burien's own freeze and snow normals.

Sprinklers → Nov 30Frozen pipes → Nov 6Ice dams → Nov 15Car battery → Dec 10Snow blower → Nov 24Sump pump → Mar 2Boat → Dec 3Motorcycle → Nov 23

See the full Burien winter checklist, in order →

Frequently asked questions

At what temperature do RV pipes freeze?
An RV's exposed plumbing and thin-walled tanks can begin to freeze once temperatures sit in the mid-20s for a few hours, sooner than a house because there is little insulation around the lines. That is why the winterizing deadline tracks the first 28°F freeze rather than the first light frost.
How much RV antifreeze do I need?
Most travel trailers and motorhomes take about two to three gallons of non-toxic RV antifreeze, and larger rigs more. Bypassing the water heater saves roughly six gallons you would otherwise waste filling the tank. Buy an extra jug; stores sell out once the first freeze warnings hit.
Can I just use my RV furnace instead of winterizing?
Relying on the furnace is risky. A propane run-out, a tripped breaker, or a dead battery during a cold night leaves the plumbing unprotected, and the furnace may not keep the underbelly and bays warm enough anyway. Draining and adding antifreeze is the dependable way to protect the system.
How do I winterize an RV water heater?
Let the tank cool and lose pressure, then drain it and, if fitted, pull the anode rod. Do not add antifreeze to the water heater tank; instead, set the bypass valves so antifreeze skips the tank and fills only the lines. Fresh antifreeze in an unbypassed heater just wastes several gallons.
When is it safe to de-winterize an RV in Burien?
Wait until the last spring freeze has passed, which averages near Mar 2 here. De-winterize by flushing the antifreeze from the lines, sanitizing the fresh tank, and checking for leaks before a trip. Reopening too early risks a surprise late freeze on a charged system.
Do I need to winterize an RV stored indoors?
A reliably heated indoor space that stays above freezing protects the plumbing, so full winterizing may not be needed. But an unheated garage or barn can still drop below freezing on a cold night. If you cannot guarantee the space stays warm, winterize to be safe.

Data: NOAA 1991–2020 normals via Seattle Tacoma Intl AP, live outlook by Open-Meteo. Sources · Methodology. Last updated: July 11, 2026.