FrostList

When to Winterize Your Boat in Yonkers, NY

ON TRACK119 days until first 28°F freezeNov 7

The first 28°F freeze near Yonkers averages November 7 (1991–2020 normals) — enough to crack an unprotected block even where owners assume they're safe — so winterize the boat by October 31. Plan for the early end: the one-in-ten date lands about 15 days before the median.

OUTLOOK

Typical first first 28°F freeze near Nov 7; local deadline about Oct 31. The live 10-day outlook loads here.

Local freeze dates for Yonkers

ThresholdEarly (1-in-10)MedianLate (9-in-10)
32°F (light freeze)Oct 10Oct 26Nov 10
28°F (hard freeze)Oct 23Nov 7Nov 23
24°F (severe)Nov 7Nov 22Dec 8

NOAA station: Dobbs Ferry-Ardsley · 6.2 mi away · 200 ft elevation.

For Yonkers, the nearest NOAA station with freeze data is Dobbs Ferry-Ardsley, 6.2 miles out at 200 feet. Median first-freeze dates there run 32°F by Oct 26, 28°F by Nov 7, 24°F by Nov 22. Year to year the 28°F date has ranged from Oct 23 to Nov 23 — about 31 days apart. Spring's last 32°F freeze clears around Apr 20. Snowfall averages 33 inches a year, first reaching an inch near December.

Expect the first frost near Oct 26 in Yonkers and the first hard freeze by about Nov 7. That first freezing night has ranged from Oct 10 to Nov 10, roughly a 31-day spread. On the spring side, the last 32°F freeze clears around Apr 20 and as late as May 6 — the green light for reopening water and de-winterizing. With around 33 inches of snow annually, plan for a handful of plowable storms each winter.

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

Yonkers freezes about a week ahead of Mount Vernon (Nov 30) and about a week ahead of New Rochelle (Nov 30) — a reminder that even nearby towns differ by days. Statewide, New York prep dates run Oct 19 through Nov 24, which is why Yonkers gets its own number rather than a New York-wide average. The same freeze also decides when to winterize an RV and store a motorcycle.

Other winter jobs in Yonkers

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

Sprinklers → Oct 28Frozen pipes → Oct 10Ice dams → Nov 15Car battery → Nov 7Snow blower → Nov 24Sump pump → Apr 20RV → Oct 28Motorcycle → Oct 26

See the full Yonkers 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 7 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 NY 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 Dobbs Ferry-Ardsley, live outlook by Open-Meteo. Sources · Methodology. Last updated: July 11, 2026.