To winterize an RV, drain every water tank and the water heater, bypass the water heater, then clear the plumbing with compressed air or pump pink RV antifreeze through every faucet, the toilet, and each drain trap. After that, pull or maintain the battery, clean out food, seal gaps against mice, and park it level with the tires protected. In Parowan, average lows dip below freezing in November, so most owners finish by late October.
Water left in your lines can freeze, expand, and crack pipes, valves, and the water pump, and you won't find the damage until spring. This guide walks through the full process step by step, for travel trailers, fifth wheels, and motorhomes, with notes on what a high-desert winter in Iron County means for an RV parked outside.
Parowan sits at about 6,155 feet. According to long-term averages from the Western Regional Climate Center's Parowan station, average lows run about 34°F in October, 24°F in November, and around 16°F to 17°F in December and January. The record low is 27 degrees below zero. December through March each average roughly 10 to 11 inches of snow.
That means three things for RV owners here:
Gather everything first so you can finish in one session. RV dealers and hardware stores in Cedar City carry all of it.
Check your owner's manual first, since plumbing layouts vary.
Empty the black tank, then the gray tank, at a dump station. Flush the black tank until the water runs clear so waste can't harden over winter and foul the sensors. Close the valves when you're done.
Open the fresh tank drain and let it empty completely. Turn off the water pump while the tank drains.
Turn the water heater off, both the electric and gas sides, and let it cool completely. Never open the drain on a hot or pressurized tank. Open a hot water faucet to relieve pressure, then remove the drain plug or anode rod and let the tank empty. If you have an anode rod, this is a good time to check it and replace it if it's mostly worn away.
Find the hot and cold low-point drain lines, usually under the RV near the frame. Open them, plus every faucet inside (hot and cold), the shower, and the outdoor shower. Flush the toilet to empty its valve. Let everything drain. Then close the faucets and the low-point drains.
Set the bypass valves so antifreeze skips the water heater. Otherwise you'll fill a 6- to 10-gallon tank with antifreeze before any reaches your faucets.
You have two main methods. Many owners in cold climates use both: blow out the lines first, then add antifreeze for extra protection.
Antifreeze method:
Compressed air method:
Plumbing is the big risk, but a few more steps keep your RV in good shape until spring.
A fully charged battery handles cold far better than a weak one, which can freeze and crack. Remove the batteries and keep them somewhere cool, dry, and above freezing on a maintainer, or charge them fully, flip the battery disconnect, and check them monthly.
Turn propane off at the tank and make sure every appliance is off. Propane tanks are on our not-allowed list (see our storage FAQ), so take removable cylinders home and store them outdoors, upright, away from your house.
Empty the fridge and freezer, clean them, and prop the doors open so mold and odors don't build up. Remove every bit of food, including sealed snacks, pet food, and anything in the cabinets. Mice look for warm, food-scented shelter in fall.
Walk around and under the RV with a flashlight and plug gaps where pipes and wires enter the floor with steel wool and foam sealant. Check that the furnace, water heater, and fridge vents have screens.
Close the blinds to cut UV fading, set a few moisture absorbers inside, and leave cabinet doors slightly open for airflow.
Inspect the roof and every seam, vent, and window seal before snow arrives, and touch up cracked sealant. Retract the slide-outs, wipe the slide seals clean, and treat them with a rubber seal conditioner if your manufacturer recommends it.
Inflate tires to the pressure listed on the sidewall or door sticker. Cover them to block high-altitude sun, which cracks rubber faster than many people expect. Use wheel chocks so you're not relying only on the parking brake for months.
For motorhomes, fill the tank, add fuel stabilizer, and run the engine a few minutes so treated fuel circulates. Do the same for the generator, and make sure engine coolant is rated for the cold.
A breathable, fitted RV cover protects paint, decals, and seals from sun and snow. A plastic tarp does the opposite: it traps moisture and rubs the finish in the wind. Strap any cover down tight and check it after big storms.
On an uncovered space, heavy snow on the roof is worth clearing when you visit, using a soft brush or foam roof rake from a safe spot. Don't climb a snowy RV roof.
If your driveway or HOA doesn't have room for the RV all winter, AA Personal Storage offers outdoor Boat/RV/Trailer parking right off I-15 in Parowan. Here's what the Rent page showed on October 20, 2026:
| Space | Monthly rate | Availability (Oct 20, 2026) | Good for |
|---|---|---|---|
| 10x30 | $30 | Only 2 left | Travel trailers, smaller fifth wheels, boats on trailers, utility trailers |
| 12x40 | $40 | Waiting list | Longer fifth wheels and motorhomes |
All of our outdoor Boat/RV/Trailer parking is uncovered. Measure your RV from hitch or bumper to bumper (including the ladder and spare tire) before you choose a size.
What you get with an outdoor space:
Outdoor spaces are not paved (our paved asphalt runs to every enclosed unit), so plan to chock the wheels and use leveling blocks if needed.
Vehicles aren't allowed inside our enclosed units, but the camp chairs, bikes, coolers, fishing gear, and bedding that ride along with your RV can go in one. A 5x10 runs $40 a month and a 10x10 $65 a month (as listed in October 2026). See what fits in a 10x10, browse our storage unit size guide, or pick up some packing tips. Keep fuel cans and propane out of the unit, since flammable materials aren't allowed.
When nighttime lows stay above freezing (in Parowan that's usually late spring), reverse the process. Close the low-point drains, return the bypass to normal, and reinstall the drain plug or anode. Fill the fresh tank and run every faucet until the water runs clear with no pink, sanitizing the system if your manual recommends it. Turn the water heater on only after it's full. Then reinstall the batteries, check the propane system for leaks, and set tire pressure before you tow.
Before the first hard freeze. Long-term averages for Parowan show October lows around 34°F and November lows around 24°F, so a single cold night in October can freeze unprotected lines. Most local owners winterize by late October, or right after their last fall trip if they camp later in the season.
Most travel trailers need about 2 to 3 gallons with the water heater bypassed. Larger fifth wheels and motorhomes with more fixtures, a washer, or an ice maker can need more, so buy an extra jug.
You can blow out the lines with compressed air at low pressure, and many owners do. But air can leave small pockets of water in low spots and traps, so most cold-climate owners still pour antifreeze into every drain trap and the toilet. Using both methods gives the most protection.
At AA Personal Storage, outdoor Boat/RV/Trailer parking was listed at $30 a month for a 10x30 space and $40 a month for a 12x40 space on October 20, 2026. Rentals are month to month with 24/7 access. All outdoor parking is uncovered.
Not at AA Personal Storage. Vehicles, including RVs, trailers, boats, ATVs, and snowmobiles, aren't allowed in enclosed units and go in our outdoor parking spaces instead. You can rent an enclosed unit nearby for camping gear and bedding.
Once your RV is winterized, give it a safe, easy-to-reach spot for the season. Call us at (435) 447-4777, email hello@aapersonalstorage.com, or reserve an outdoor RV space online in a few minutes. You'll find us at 450 N 600 W in Parowan, just off I-15. We're about 20 miles north of Cedar City and an easy drive from Enoch, Paragonah, Summit, and Brian Head (about 12.7 miles down UT-143). Get directions to our facility or check the layout on our facility map. AA Personal Storage is locally owned, with 24/7 access and month-to-month rentals for all of Iron County.
