FrostList

When to Winterize Your RV in Des Moines, IA

ON TRACK111 days until first 28°F freezeOct 30

Aim to winterize your RV in Des Moines by October 20, roughly a week and a half before the median first 28°F freeze of October 30, which one fall in ten shows up by October 16. It's a short step from frost to a hard freeze: roughly 10 days on average.

OUTLOOK

Typical first first 28°F freeze near Oct 30; local deadline about Oct 20. The live 10-day outlook loads here.

Local freeze dates for Des Moines

ThresholdEarly (1-in-10)MedianLate (9-in-10)
32°F (light freeze)Oct 4Oct 20Nov 1
28°F (hard freeze)Oct 16Oct 30Nov 11
24°F (severe)Oct 25Nov 6Nov 21

NOAA station: Des Moines Intl AP · 5.1 mi away · 957 ft elevation.

Des Moines draws its numbers from Des Moines Intl AP, 957 feet up and 5.1 miles away. Its median first-freeze dates are 32°F by Oct 20, 28°F by Oct 30, 24°F by Nov 6. Year to year the 28°F date has ranged from Oct 16 to Nov 11 — about 26 days apart. Spring's last 32°F freeze clears around Apr 18. Snowfall averages 36 inches a year, first reaching an inch near November.

Des Moines usually sees its first 32°F night about Oct 20, with the first 28°F hard freeze close behind near Oct 30. Year to year, the first 32°F night has fallen anywhere from Oct 4 to Nov 1 — about 28 days apart. Spring's final freeze lands near Apr 18 and as late as May 2, so that is when outdoor water and stored gear can safely come back online. Snowfall averages roughly 36 inches a year — enough that a working snow blower and a clear roof edge earn their keep.

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

Compared with nearby cities, Des Moines's first-freeze date near Oct 30 sits close to West Des Moines (Oct 30) and close to Urbandale (Oct 30). Iowa's deadlines span Oct 8 to Oct 22 statewide — one date for all of Iowa would be off by weeks for Des Moines. Once you know Des Moines's freeze date, use it to shut down your sprinklers and winterize a boat too.

Other winter jobs in Des Moines

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

Sprinklers → Oct 20Frozen pipes → Oct 4Ice dams → Oct 16Car battery → Oct 30Snow blower → Oct 25Sump pump → Apr 18Boat → Oct 23Motorcycle → Oct 20

See the full Des Moines 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 Des Moines?
Wait until the last spring freeze has passed, which averages near Apr 18 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 Des Moines Intl AP, live outlook by Open-Meteo. Sources · Methodology. Last updated: July 11, 2026.