FrostList

When to Winterize Your RV in Detroit, MI

ON TRACK121 days until first 28°F freezeNov 9

In a typical year, winterize your RV in Detroit by October 30. The median first 28°F hard freeze at Detroit's NOAA station is November 9 (1991–2020 normals); one year in ten it arrives as early as October 29. Cold deepens quickly here — only about 9 days separate the first frost from that hard freeze.

OUTLOOK

Typical first first 28°F freeze near Nov 9; local deadline about Oct 30. The live 10-day outlook loads here.

Local freeze dates for Detroit

ThresholdEarly (1-in-10)MedianLate (9-in-10)
32°F (light freeze)Oct 17Oct 31Nov 11
28°F (hard freeze)Oct 29Nov 9Nov 23
24°F (severe)Nov 6Nov 21Dec 7

NOAA station: Detroit City AP · 5.7 mi away · 626 ft elevation.

The reference station for Detroit is Detroit City AP (5.7 mi, 626 ft). First freeze there: 32°F by Oct 31, 28°F by Nov 9, 24°F by Nov 21. The 28°F freeze has come as early as Oct 29 and as late as Nov 23, a 25-day spread. Spring's last 32°F freeze clears around Apr 21. Snowfall averages 28 inches a year, first reaching an inch near December.

In Detroit, freezing nights (32°F) typically begin around Oct 31 and the first hard freeze (28°F) follows near Nov 9. That first freezing night has ranged from Oct 17 to Nov 11, roughly a 25-day spread. On the spring side, the last 32°F freeze clears around Apr 21 and as late as May 6 — the green light for reopening water and de-winterizing. With around 28 inches of snow annually, plan for a handful of plowable storms each winter.

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

Against its neighbors, Detroit (first freeze Nov 9) runs close to Dearborn (Nov 6) and later than Lincoln Park (Oct 28). Across Michigan, local prep deadlines in our data range from Oct 13 to Oct 30, so a statewide rule of thumb would miss Detroit by weeks. In Detroit, that same cold is your cue to shut down your sprinklers and winterize a boat.

Other winter jobs in Detroit

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

Sprinklers → Oct 30Frozen pipes → Oct 17Ice dams → Nov 15Car battery → Nov 9Snow blower → Nov 24Sump pump → Apr 21Boat → Nov 2Motorcycle → Oct 31

See the full Detroit 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 Detroit?
Wait until the last spring freeze has passed, which averages near Apr 21 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 Detroit City AP, live outlook by Open-Meteo. Sources · Methodology. Last updated: July 11, 2026.