Pool closing · Texas
When to Close Your Pool in Spring, TX: Deadline, Window & Checklist
Last updated: July 15, 2026 · Model window year: 2026 · dates · checklist · FAQ
In Spring, the closing window runs from November 18 to November 28. Let the water cool out of the algae-growth range before covering — close too warm and you lift the cover onto a green surprise in spring — but finish ahead of the first freeze, which normals place around December 9. The live estimate below shows where Spring's water sits today.
Spring closing dates at a glance
| Closing window | November 18 – November 28 |
|---|---|
| Close by (deadline) | November 28 |
| First freeze, 50% probability | December 9 |
| Open by (recommended) | February 17 |
| Opening window | February 10 – March 3 |
| 61°F crossing (7-day mean) | March 3 |
| Swim-season length (80°F+ days) | 193 days |
| NOAA normals station | Houston Intercont Airport · 5.8 mi · 95 ft |
Closing is close to optional here — many Spring owners trade the cover for shorter pump hours and swim the shoulder seasons. If you do close, the late window above still applies.
Four water checkpoints anchor Spring's year in the model: mid-April at about 69°F, mid-June at 82°F, mid-August near the 86°F peak zone, and mid-October easing through 74°F. The dates in the table are where those numbers cross the thresholds that matter.
The 12-step Spring 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
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.
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Deep-clean the pool
Make the last cleaning the best one of the year: full skim, full brush, careful vacuum. Debris left behind steeps all winter and greets you as April's water problem.
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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
Check the cover manufacturer's spec before touching the hose: solid covers typically want water below the skimmer mouth, mesh often barely lower than normal. Full draining is off the table entirely.
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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.
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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
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.
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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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Note this year's dates
Jot down when Spring's water actually cooled and when you closed. A two-line note beats memory next November 18 — your own yard runs a few days off any model, including ours.
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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
A small stack of supplies turns the checklist above into a single-weekend job. Buy before Spring's November rush and the whole list ships at leisure instead of sprinting.
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Air pillow
A soft target for the ice sheet, centered under the cover.
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Winter cover
The one purchase every other closing step depends on.
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Cover pump
Keeps rain and melt off a solid cover all season.
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Expansion plugs + skimmer guard
Cheap rubber that stands between ice and your fittings.
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Pool antifreeze
Pool-rated glycol for the lines air couldn't clear.
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Winter closing kit
Closing chemistry in one box, dosed by pool volume.
How Spring compares locally
Statewide context: across the 68 Texas cities we model, Spring's November 28 deadline sits in the earliest quarter. Nearby, The Woodlands (11 mi) closes around November 24 and Atascocita (13 mi) around November 28 — treat gaps under a week as microclimate noise, not strategy. Spring planning restarts at the opening guide; the Spring pool season page keeps the whole year in one view.
Every number on this page traces to one instrument cluster: Houston Intercont Airport, 5.8 miles south of Spring's center at an elevation near 95 feet. NOAA computed its 1991–2020 normals from roughly three decades of daily readings — long enough that one strange spring in Harris County barely moves the dates.
Field notes for Spring owners
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.
Blowout first, antifreeze second
Air is the only guaranteed freeze protection: a line that's verifiably dry cannot burst. Antifreeze (pool-grade, per label) is the fallback for lines you can't confirm — long runs, low spots, water-feature plumbing. Doing antifreeze instead of a blowout, rather than in addition, is how most cracked returns happen.
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.
The case for a shorter off-season
Spring's climate leaves water usable well past most owners' patience. If the family still swims in November, don't rush the cover — the model window runs to November 28 for a reason. Closing late and cold beats closing early and warm in every spring-condition metric that matters.
Spring pool closing FAQ
What temperature should water be to close a pool?
Cold enough that biology has clocked out — below 65°F and falling, ideally low 60s. The widget above tracks Spring's actual water; the normals say the durable cool-down arrives near November 18, and anything inside the window to November 28 closes clean.
Can you close a pool too early?
Yes — it's the most common closing mistake. Seal 70°F water under a cover and algae keep growing in the dark all autumn; the spring opening turns green and expensive. In Spring, hold off until the cool-down near November 18 before covering.
Do I need antifreeze in pool lines?
Only where water might remain. If every line is properly blown out and plugged, air is the antifreeze. Lines you can't verify dry — long runs, low spots, water features — get pool-grade antifreeze dosed per its label. With Spring's first freeze normal near December 9, don't leave that question open.
How far should I drain my pool for winter?
Only to the line your cover manufacturer prints — a few inches below the skimmer for most solid covers, close to operating level for many mesh designs with the skimmer plugged. The water you leave in is structural: it holds the shell against groundwater all winter.
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. Spring 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 Spring?
Treat November 28 as the deadline in Spring. It's derived from the 1991–2020 normals: the cool-down plus ten days (the freeze normal, December 9, leaves room to spare). Weather varies year to year, so watch the 10-day forecast in late November — an early cold snap moves the real deadline, and the widget above flags exactly that.
Email me when Spring hits the closing window
Data: NOAA 1991–2020 climate normals via Houston Intercont Airport (5.8 mi); live outlook by Open-Meteo. Full attribution on the sources page. Model assumptions and error bars on methodology.