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Pool closing · Nevada

When to Close Your Pool in Las Vegas, NV: Deadline, Window & Checklist

Last updated: July 15, 2026 · Model window year: 2026 · dates · checklist · FAQ

Circle November 14 on the Las Vegas calendar. Closing earlier traps warm, algae-friendly water under the cover; closing later gambles the plumbing against the first freeze, which the 1991–2020 normals place near December 10. The window opens November 4 — the live widget below shows how this year is actually tracking against it.

Live water estimate

SEASONAL VIEW

Estimated unheated pool water temp (site model, ±5°F). The live estimate loads in your browser from Open-Meteo air temperatures; in a typical year Las Vegas water runs about 47°F at its winter floor and 92°F at its summer peak.

40 45 50 55 60 65 70 75 80 85 58 open 65 algae

Las Vegas closing dates at a glance

Site model of NOAA 1991–2020 daily normals for Las Vegas Air Terminal (4.2 mi from Las Vegas city center). Dates are typical-year guidance, not forecasts.
Closing windowNovember 4 – November 14
Close by (deadline)November 14
First freeze, 50% probabilityDecember 10
Open by (recommended)March 9
Opening windowMarch 2 – March 23
61°F crossing (7-day mean)March 23
Swim-season length (80°F+ days)177 days
NOAA normals stationLas Vegas Air Terminal · 4.2 mi · 2203 ft

Las Vegas's 177-day warm season leaves comfortable margins on both ends — the windows above aim you at the cheap-chemistry versions of each transition.

Four water checkpoints anchor Las Vegas's year in the model: mid-April at about 65°F, mid-June at 84°F, mid-August near the 91°F peak zone, and mid-October easing through 72°F. The dates in the table are where those numbers cross the thresholds that matter.

The 12-step Las Vegas winterizing checklist

The order matters more than the date: balanced water first, verified-dry lines before anything else freezes-proofs, and the cover only after everything below it is done. Work the list inside the window above.

  1. Balance the water a few days ahead

    Give the chemistry a head start — balance to label ranges several days out, while circulation can still mix corrections evenly. Closing-day dosing never distributes as well.

  2. Deep-clean the pool

    Brush, skim, and vacuum like company's coming. A pool that goes under the cover spotless comes out needing a rinse; one that goes under dirty comes out needing a project.

  3. Service the filter one last time

    Clean media goes into storage, dirty media comes out worse: backwash the sand or DE, rinse the cartridges, all per the manual, before anything drains.

  4. Apply winter chemicals per label

    Winter chemicals go in before shutdown, not after: label-dosed, circulated for a few hours, distributed evenly. A floater dropped on still water protects one corner.

  5. Lower the water level

    Drop the level as your cover manufacturer specifies — typically below the skimmer mouth for solid covers. Never drain a pool fully; groundwater pressure can damage the shell.

  6. Blow out the lines and plug returns

    Push air through skimmer, return, and cleaner lines until they run dry mist, then seat expansion plugs at each return while air still flows. This is the single most important freeze-protection step.

  7. Protect the skimmer

    Give the skimmer something cheap to break: a guard bottle or rated plug absorbs the ice expansion that would otherwise split the housing.

  8. Add pool antifreeze where blowouts fall short

    Any line you can't prove is dry gets pool-grade antifreeze at the label's rate per foot. Automotive antifreeze is toxic in this context — pool-rated only, always.

  9. Drain the equipment

    Open the drains on everything that holds water and let the pad empty completely. Cartridges and small equipment overwinter far better on a garage shelf than outside.

  10. Set the air pillow and cover

    Float a centered air pillow, then land the cover and secure it the way its design intends — bags, cable, or straps. Ice sheets need somewhere to collapse inward, and the pillow is that somewhere.

  11. Remove and store ladders and rails

    Pull ladders, rails, and the diving-board hardware; rinse, dry, and store them out of the weather. Anchor sockets get a dab of protectant so spring bolts turn freely.

  12. Winterize the water features

    Waterfalls, slides, and spillover spas hold water in places gravity won't clear — blow those lines separately and plug them, or they'll be the one crack you find in spring.

What to buy before the rush

A small stack of supplies turns the checklist above into a single-weekend job. Buy before Las Vegas's November rush and the whole list ships at leisure instead of sprinting.

  • Expansion plugs + skimmer guard

    Cheap rubber that stands between ice and your fittings.

  • Pool antifreeze

    Backup for unverifiable lines; label rate per foot of pipe.

  • Winter closing kit

    The under-the-cover chemistry, measured for your gallons.

  • Air pillow

    A soft target for the ice sheet, centered under the cover.

  • Winter cover

    Sized to overlap; the cheapest insurance the pool wears all winter.

  • Cover pump

    Standing water is a cover killer; this is the counter.

How Las Vegas compares locally

Las Vegas closes in the later half of Nevada's calendar. Neighbors run close: Spring Valley (10 mi away) models its deadline at November 13 (1 day earlier vs Las Vegas's November 14), while North Las Vegas (11 mi) shows November 17. The spring mirror of this page is the Las Vegas opening guide, and the season overview draws both windows on a single bar.

Local means local: Las Vegas's dates come from Las Vegas Air Terminal, the nearest station with complete daily temperature normals — 4.2 miles east, about 2203 feet up. Between that station and a Clark County backyard there's always a degree or two of microclimate; the windows are built wide enough to carry it.

Field notes for Las Vegas owners

Cold water is the whole point

A pool closed at 55°F barely changes all winter: algae are dormant, chemicals hold, and spring opens with a light dusting instead of a bloom. A pool closed at 72°F runs its own quiet ecosystem under the cover for a month. The date matters less than the water temperature it represents.

Cover pumps die in the cold — plan for it

A cover pump left running into a hard freeze can lock in ice and burn out. On freezing forecasts, pull it, let the storm pass, and put it back for the melt. Automatic models with freeze protection earn their price in exactly one forgotten weekend.

The fifteen-minute monthly walk-around

Once a month all winter: pump or siphon standing water off solid covers, re-tension straps or top up water bags, confirm the level hasn't dropped enough to strand the cover, and glance at the pad for critter nests. Every major cover failure starts as a skipped walk-around.

Don't close a pool people are still using

With Las Vegas's long season, the question isn't "is it November?" but "has the water actually cooled?" The window running to November 14 exists because warm-water closings breed spring algae. If swimmers keep showing up through November, let them — patience here is free maintenance.

Las Vegas pool closing FAQ

What temperature should water be to close a pool?

The practical target is water in the low 60s°F or below at closing day. Our Las Vegas model has the sustained cool-down starting November 4; closing between then and November 14 means chemistry stays put and the spring reveal is a mild one.

Can you close a pool too early?

Early closing is the mistake the whole model is built to prevent from the other direction. A cover installed over 70°F water is a terrarium: sanitizer decays, algae compound, nobody looks for months. Las Vegas's water isn't reliably out of that zone until about November 4 — the calendar's first cold weekend doesn't change that.

Do I need antifreeze in pool lines?

Blown-out, plugged lines don't need it; doubtful lines do. Use only antifreeze labeled for pools, at the label's rate per foot of pipe — never automotive antifreeze. In Las Vegas the freeze clock starts around December 10, so settle this during closing, not during the first cold snap.

How far should I drain my pool for winter?

Follow the cover's instructions first: solid covers usually want water a few inches below the skimmer; some mesh setups run higher with the skimmer sealed. The hard rule is never empty — hydrostatic pressure can lift or crack an empty pool, a far worse outcome than any freeze.

What happens if you don't winterize a pool?

Two failure modes. Where freezes reach the plumbing, expansion cracks pumps, filters, and fittings from the inside. Where they don't, an unwatched pool simply drifts green and unbalanced by spring. Las Vegas has no published freeze normal to pin the date, so the winterizing above plus forecast-watching covers both risks.

When is the last safe date to close in Las Vegas?

November 14, by our model — the cool-down plus ten days (the freeze normal, December 10, leaves room to spare). Later closes happen, but they happen in gloves. The winterizing steps above take a weekend; leave yourself at least that much runway before Las Vegas's first freeze-risk stretch.

Data: NOAA 1991–2020 climate normals via Las Vegas Air Terminal (4.2 mi); live outlook by Open-Meteo. Full attribution on the sources page. Model assumptions and error bars on methodology.