FrostList

When to Winterize Your Boat in Bountiful, UT

ON TRACK116 days until first 28°F freezeNov 4

The first 28°F freeze near Bountiful averages November 4 (1991–2020 normals) — enough to crack an unprotected block even where owners assume they're safe — so winterize the boat by October 28. Cold deepens quickly here — only about 11 days separate the first frost from that hard freeze.

OUTLOOK

Typical first first 28°F freeze near Nov 4; local deadline about Oct 28. The live 10-day outlook loads here.

Local freeze dates for Bountiful

ThresholdEarly (1-in-10)MedianLate (9-in-10)
32°F (light freeze)Oct 9Oct 24Nov 7
28°F (hard freeze)Oct 20Nov 4Nov 18
24°F (severe)Oct 29Nov 14Nov 29

NOAA station: Bountiful Bench · 1.6 mi away · 4,950 ft elevation.

Bountiful draws its numbers from Bountiful Bench, 4,950 feet up and 1.6 miles away. Its median first-freeze dates are 32°F by Oct 24, 28°F by Nov 4, 24°F by Nov 14. That hard freeze has landed anywhere from Oct 20 to Nov 18, a swing of roughly 29 days. Spring's last 32°F freeze clears around Apr 25. Snowfall averages 119 inches a year, first reaching an inch near October.

In Bountiful, freezing nights (32°F) typically begin around Oct 24 and the first hard freeze (28°F) follows near Nov 4. That first freezing night has ranged from Oct 9 to Nov 7, roughly a 29-day spread. On the spring side, the last 32°F freeze clears around Apr 25 and as late as May 14 — the green light for reopening water and de-winterizing. Snow totals near 119 inches a year mean plowing and ice-dam control share the winter to-do list here.

Your boat checklist

  1. Change the engine oil and filter while the motor is warm so contaminants leave with the old oil.
  2. Run the engine on antifreeze until pink fluid reaches the outlet, protecting the block and manifolds.
    Helpful gear: Marine antifreeze — Recommended pick
  3. Fog the cylinders with fogging oil as the engine runs down to coat internal parts against corrosion.
    Helpful gear: Fogging oil — Recommended pick
  4. Top off the fuel tank and add stabilizer to limit condensation and protect ethanol-blend fuel.
    Helpful gear: Marine fuel stabilizer — Recommended pick
  5. Drain the raw-water system, the livewell, and any washdown lines that can trap water.
  6. Remove the battery, charge it fully, and keep it on a maintainer over the layup.
    Helpful gear: Battery maintainer — Recommended pick
  7. Support the cover so snow and rain shed off, and leave vents so the interior can breathe.
  8. For an inboard or sterndrive, follow the manual closely — those blocks are the ones freeze claims hit hardest.

What to have on hand

Marine antifreeze
Propylene-glycol fluid rated for engine blocks and systems.
Recommended pick
Marine fuel stabilizer
Additive that protects ethanol-blend fuel over the layup.
Recommended pick
Fogging oil
Spray that coats cylinders against corrosion in storage.
Recommended pick
Battery maintainer
Keeps the cranking battery topped off on the trailer.
Recommended pick

What this means locally

Against its neighbors, Bountiful (first freeze Nov 4) runs about a week ahead of Salt Lake City (Nov 18) and close to Layton (Nov 1). Across Utah, local prep deadlines in our data range from Oct 7 to Nov 13, so a statewide rule of thumb would miss Bountiful by weeks. In Bountiful, that same cold is your cue to winterize an RV and store a motorcycle.

Other winter jobs in Bountiful

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

Sprinklers → Oct 25Frozen pipes → Oct 9Ice dams → Sep 15Car battery → Nov 4Snow blower → Sep 24Sump pump → Apr 25RV → Oct 25Motorcycle → Oct 24

See the full Bountiful winter checklist, in order →

Frequently asked questions

At what temperature does a boat engine block crack?
Trapped water in an engine block or manifold can freeze and crack the casting once temperatures fall below 32°F and stay there long enough. Inboard and sterndrive blocks hold the most water and are the most vulnerable. Draining fully and adding antifreeze before the first hard freeze near Nov 4 is the protection.
Do outboards need winterizing?
Yes. An outboard should be drained so no water sits in the powerhead or lower unit, and the fuel system stabilized. Outboards self-drain better than inboards when tilted down, but fogging the cylinders and changing the gear oil are still part of a proper layup.
Fogging oil: is it necessary?
Fogging coats the cylinder walls and internal parts with a film that resists corrosion during months of storage. On engines that sit all winter it is cheap insurance against rust, especially in humid or coastal storage. Follow your engine maker's guidance on how to apply it.
How much does boat winterization cost?
A professional winterization varies with engine type and boat size, and inboards cost more than a simple outboard. Doing it yourself costs mainly antifreeze, oil, and fogging oil. Either way, the bill is far smaller than repairing a cracked block, which is the failure winterizing prevents.
Do boats in UT really need winterizing?
If temperatures reach freezing where the boat is stored, yes. Freeze claims are common in milder states precisely because owners assume they are safe and skip the step, then a rare cold snap cracks a block. Check the local freeze dates above and protect the engine before the first hard freeze.
When should I de-winterize my boat?
De-winterize in spring once the risk of a hard freeze has passed for your area. Reconnect and charge the battery, replace drain plugs, check hoses and clamps, and inspect the fuel system before the first launch. Reopening too early leaves the block exposed to a late cold snap.

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