FrostList

When to Winterize Your Boat in Mansfield, TX

ON TRACK146 days until first 28°F freezeDec 4

Plan to haul out and winterize your boat in Mansfield by November 27. The first 28°F freeze near Mansfield averages December 4 in the 1991–2020 normals, and freeze damage often surprises owners in milder states. Cold deepens quickly here — only about 13 days separate the first frost from that hard freeze.

OUTLOOK

Typical first first 28°F freeze near Dec 4; local deadline about Nov 27. The live 10-day outlook loads here.

Local freeze dates for Mansfield

ThresholdEarly (1-in-10)MedianLate (9-in-10)
32°F (light freeze)Nov 3Nov 21Dec 7
28°F (hard freeze)Nov 14Dec 4Dec 30
24°F (severe)Nov 27Dec 23Jan 24

NOAA station: Arlington Muni AP · 7.5 mi away · 630 ft elevation.

Numbers for Mansfield come from Arlington Muni AP, 7.5 miles away at 630 feet, where the medians fall 32°F by Nov 21, 28°F by Dec 4, 24°F by Dec 23. That hard freeze has landed anywhere from Nov 14 to Dec 30, a swing of roughly 46 days. Spring's last 32°F freeze clears around Mar 9. Snowfall averages 0 inches a year.

In Mansfield, freezing nights (32°F) typically begin around Nov 21 and the first hard freeze (28°F) follows near Dec 4. That first freezing night has ranged from Nov 3 to Dec 7, roughly a 34-day spread. On the spring side, the last 32°F freeze clears around Mar 9 and as late as Mar 28 — the green light for reopening water and de-winterizing. With almost no snow in a normal year, cold — not plowing — sets the calendar, and it centers on Mar 9.

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 antifreezeRecommended pick
  3. Fog the cylinders with fogging oil as the engine runs down to coat internal parts against corrosion.
    Helpful gear: Fogging oilRecommended pick
  4. Top off the fuel tank and add stabilizer to limit condensation and protect ethanol-blend fuel.
    Helpful gear: Marine fuel stabilizerRecommended 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 maintainerRecommended 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, Mansfield (first freeze Dec 4) runs later than Burleson (Nov 25) and later than Cedar Hill (Nov 25). Across Texas, local prep deadlines in our data range from Jan 1 to Dec 29, so a statewide rule of thumb would miss Mansfield by weeks. In Mansfield, that same cold is your cue to winterize an RV and store a motorcycle.

Other winter jobs in Mansfield

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

See the full Mansfield 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 Dec 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 TX 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 Arlington Muni AP, live outlook by Open-Meteo. Sources · Methodology. Last updated: July 11, 2026.