Pool closing · Pennsylvania
When to Close Your Pool in Scranton, PA: Deadline, Window & Checklist
Last updated: July 15, 2026 · Model window year: 2026 · dates · checklist · FAQ
Two dates decide a Scranton closing: September 25, when the 7-day mean drops back through 61°F and the water goes algae-quiet, and October 5, the model deadline set a safe week ahead of the October 20 first-freeze normal. Everything on this page — live water estimate, window, winterizing sequence — exists to land you between them.
Scranton closing dates at a glance
| Closing window | September 25 – October 5 |
|---|---|
| Close by (deadline) | October 5 |
| First freeze, 50% probability | October 20 |
| Open by (recommended) | May 2 |
| Opening window | April 25 – May 16 |
| 61°F crossing (7-day mean) | May 16 |
| Swim-season length (80°F+ days) | 77 days |
| NOAA normals station | Wilkes-barre International Airport · 5.8 mi · 930 ft |
Scranton banks only about 77 days of 80°F-plus afternoons — early opening weeks are the cheapest season extension available.
Four water checkpoints anchor Scranton's year in the model: mid-April at about 48°F, mid-June at 68°F, mid-August near the 72°F peak zone, and mid-October easing through 56°F. The dates in the table are where those numbers cross the thresholds that matter.
The 12-step Scranton 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.
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Balance the water a few days ahead
Do the chemistry midweek, close on the weekend: alkalinity and pH into label ranges with days of circulation left to spread them. Winter locks in whatever state the water holds on closing day.
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Deep-clean the pool
Leave nothing organic behind: skim the surface, brush every wall and step, vacuum the floor slowly. What goes under the cover dirty comes out worse — winter only ever compounds what it's given.
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Service the filter one last time
Send the filter into winter clean: backwash the sand or DE, rinse and dry the cartridges indoors. Media stored dirty over winter hardens into a spring problem no backwash fixes.
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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.
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Lower the water level
Your cover's manual sets the number — commonly a few inches under the skimmer for solid covers, barely below normal for mesh. Stop there. The remaining water isn't laziness; it's ballast holding the shell in the ground.
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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.
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Protect the skimmer
The skimmer throat is where trapped water has no escape — park a guard bottle or rated plug in it and let ice crush the cheap part.
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Add pool antifreeze where blowouts fall short
Doubt is the criterion: any run you can't confirm dry gets pool-grade antifreeze at the label's per-foot rate. The automotive jug from the garage is for cars — it has no business in pool plumbing.
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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.
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Set the air pillow and cover
Center an inflated air pillow, then fit the cover and secure it with water bags, cable, or straps as designed. The pillow gives ice a place to push besides your walls.
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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.
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Calendar the off-season checks
Set a monthly reminder from October 5 to spring: check cover tension, pump off standing water, and glance at the water level. Fifteen minutes a month protects the whole closing job.
What to buy before the rush
The September crowd empties shelves in a predictable order. This is the short list worth owning before Scranton's window opens — nothing exotic, just the stuff everyone needs the same weekend.
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Expansion plugs + skimmer guard
Seals blown-out lines and sacrifices itself to skimmer ice.
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Pool antifreeze
Backup for unverifiable lines; label rate per foot of pipe.
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Winter closing kit
Closing chemistry in one box, dosed by pool volume.
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Air pillow
A soft target for the ice sheet, centered under the cover.
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Winter cover
Sized to overlap; the cheapest insurance the pool wears all winter.
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Cover pump
Keeps rain and melt off a solid cover all season.
How Scranton compares locally
Two nearby data points to triangulate with: Binghamton, 50 miles from Scranton, models its close at September 23 (roughly two weeks earlier); Bethlehem, 56 miles out, at October 9. Scranton's own window ends October 5. For the other half of the calendar see when to open in Scranton, or scan the full year on the season page.
The measuring stick here is Wilkes-barre International Airport — 5.8 miles to the southwest, elevation about 930 feet. Its 1991–2020 record is what the model reads for Scranton; your backyard in Lackawanna County will run a touch warmer or cooler with shade, wind, and pavement, which is exactly the slack the two-week lead absorbs.
Field notes for Scranton owners
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.
What comes indoors
Cartridges, the cover pump when idle, chemical containers, and anything with a small motor overwinter better in the garage. Cold cycling is hard on plastics and seals; shelf space is cheaper than replacements. Label a single bin now and spring assembly becomes a scavenger hunt with a map.
The mesh-cover spring surprise, prevented in fall
Mesh-covered pools green up early because late-winter sun plus nutrient-carrying meltwater reaches the water. The fall counter-moves: close late and cold, dose the winter kit exactly per label, and plan an early-spring peek under the cover rather than a Memorial Day reveal.
Closing for a real winter
A Scranton closing has to hold for months of freeze-thaw, not a few frosty mornings. Spend the effort where winters bite: prove every line dry, drain every vessel on the pad, guard the skimmer, and tension the cover for wind that will actually come. The reward is a spring opening that's a rinse, not a rebuild.
Scranton pool closing FAQ
What temperature should water be to close a pool?
Close once water holds below about 65°F — the point where algae go mostly dormant — and before hard freezes. In Scranton, the 7-day mean drops through the threshold around September 25, so the window between then and October 5 is the sweet spot for a clean, stable close.
Can you close a pool too early?
You can, and warm-water closings are why "we opened to a swamp" stories exist. The fix is patience: let Scranton's water cool through the mid-60s°F — around September 25 by our model — then close inside the window that ends October 5.
Do I need antifreeze in pool lines?
It depends entirely on your confidence in the blowout. Lines that blew fully dry need nothing; anything uncertain — low runs, water features, a stubborn cleaner line — gets pool-grade antifreeze at the label's rate per foot. With Scranton's freeze clock starting near October 20, uncertainty is the thing to eliminate.
How far should I drain my pool for winter?
Less than most people think. Below the skimmer opening is the classic solid-cover target; mesh covers often specify higher water. The cover's own manual wins every argument, and "drain it completely" is never the answer — empty shells pop out of wet ground.
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. Scranton 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 Scranton?
Our model's practical deadline is October 5 — set by the cool-down plus ten days (the freeze normal, October 20, leaves room to spare). Push much past it and you're winterizing in freeze-warning weather, rushing the blowout, and hoping the cover goes on before the first hard night. Inside the September 25–October 5 window, none of that drama applies.
Email me when Scranton hits the closing window
Data: NOAA 1991–2020 climate normals via Wilkes-barre International Airport (5.8 mi); live outlook by Open-Meteo. Full attribution on the sources page. Model assumptions and error bars on methodology.