When to Close Your Pool in Logan, UT: Deadline, Window & Checklist

Logan closing dates at a glance

A short season cuts both ways: every week opened before June 7 is a real slice of Logan's roughly 83-day warm-swim budget.

At roughly 4475 ft, Logan Radio Kvnu runs cooler than lowland forecasts for the same region — trust these local numbers over metro-wide weather graphics.

Four water checkpoints anchor Logan's year in the model: mid-April at about 45°F, mid-June at 62°F, mid-August near the 72°F peak zone, and mid-October easing through 51°F. The dates in the table are where those numbers cross the thresholds that matter.

The 12-step Logan winterizing checklist

A closing is a plumbing project with a chemistry warm-up. Start a few days ahead of your target date, keep every dose per its product label, and don't skip the photographs — spring-you reassembles from them.

1. Balance the water a few days ahead

   Start midweek for a weekend close: bring alkalinity and pH into their label ranges and let the water settle. What you seal under the cover is what the pool soaks in until spring.

2. Deep-clean the pool

   Skim, brush walls and steps, and vacuum carefully. Any leaves or algae you seal under the cover become spring's chemistry problem, so closing day cleanliness pays twice.

3. Service the filter one last time

   Backwash sand or DE, or pull and rinse cartridges, per the manual. A filter stored dirty cakes over winter and starts spring half-clogged.

4. Apply winter chemicals per label

   Dose the winter kit while the pump still runs — every product exactly per its label for your volume — so the chemistry is fully mixed before the system goes quiet.

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

   Air through every line — skimmer, returns, cleaner — until each blows dry mist, plugging returns while the air still pushes. Nothing else on this list protects as much plumbing per minute.

7. Protect the skimmer

   Seat a skimmer guard or bottle in the throat — ice that forms there needs a sacrifice, and a two-dollar bottle beats a plumbing repair under the deck.

8. Add pool antifreeze where blowouts fall short

   Antifreeze is the insurance policy for doubtful lines, not a replacement for the blowout: pool-grade product, label dosing, and only where air couldn't finish the job.

9. Drain the equipment

   Every vessel on the pad — pump, filter, heater, chlorinator — gets its drain plugs pulled. Drop all the plugs in the pump basket; that's the one place everyone looks first in spring.

10. Set the air pillow and cover

    Inflate the pillow to about two-thirds, center it, then bring the cover over and secure it per its design. Under ice, that soft dome is the difference between inward compression and outward wall pressure.

11. Shut down the heater carefully

    Follow the manufacturer's winterizing sequence for your heater — drain it fully and, for gas units, close the supply valve. Heat exchangers are the most expensive freeze casualty on the pad.

12. Stage the cover pump

    Solid covers need drainage all winter: set a cover pump or siphon before the first storm, not after. Standing water strains seams and invites a mid-winter emergency.

What to buy before the rush

The September crowd empties shelves in a predictable order. This is the short list worth owning before Logan's window opens — nothing exotic, just the stuff everyone needs the same weekend.

• Winter closing kit

  Season-length winter chemicals in one label-dosed box.

• Air pillow

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

• Winter cover

  The one purchase every other closing step depends on.

• Cover pump

  Keeps rain and melt off a solid cover all season.

• Expansion plugs + skimmer guard

  The blowout's finishing move — one per return, one for the skimmer.

• Pool antifreeze

  Pool-rated glycol for the lines air couldn't clear.

How Logan compares locally

Two nearby data points to triangulate with: Ogden, 36 miles from Logan, models its close at October 9 (roughly two weeks later); Layton, 46 miles out, at October 4. Logan's own window ends September 25. For the other half of the calendar see when to open in Logan, or scan the full year on the season page.

Every number on this page traces to one instrument cluster: Logan Radio Kvnu, 0.8 miles southwest of Logan's center at an elevation near 4475 feet. NOAA computed its 1991–2020 normals from roughly three decades of daily readings — long enough that one strange spring in Cache County barely moves the dates.

Field notes for Logan 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.

Salt cells overwinter indoors

Remove the cell at closing, inspect and clean per the manufacturer, and store it inside with the unions capped. A dummy cell or spacer keeps the plumbing sealed. Cells left in outdoor plumbing through freezes are a common — and completely avoidable — spring casualty.

Leaf season vs closing day

If your yard drops serious leaves, the cheap trick is a leaf net over the main cover through the drop, then one bulk removal before snow. Leaves that winter on (or worse, under) the cover steep like tea and hand you stained water and clogged pumps in spring.

Hard-winter homework

Where winter is long — Logan banks only about 83 warm-swim days — the closing carries months of load. Bury the effort where it counts: verified-dry lines, fully drained equipment, a skimmer guard, and a cover secured for real wind. A short season forgives a late opening; it never forgives a cracked pump.

Altitude closing notes

Elevation compresses Logan's closing window: at about 4475 ft, radiational cooling can drop a clear night below freezing while afternoons still feel like pool weather. Trust the first-freeze normal (October 2) over the vibe, stage the blowout gear early, and treat any clear-sky cold front in September as your cue.