PoolWindow

Pool season · Texas

Lewisville Pool Season: the Year on One Bar

Last updated: July 15, 2026 · dates · water temp

One bar, one year, one Lewisville pool. The season bar below draws everything the model knows — opening window, prime season, closing window — against today's date, with the working details one click away on the opening and closing pages.

J F M A M J J A S O N D today (build date)

off-season opening window swim season closing window

Reading it takes ten seconds: 52 dots, one per week. Solid teal is Lewisville's swim season; the hollow teal run before it (March 11 to April 1) is when to open; the hollow amber run after is when to close, with November 9 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Lewisville pool calendar

March 18open by
November 9close by
15780°F+ days
86°Fwater peak

Opening — target March 18

Target March 18; the practical window runs March 11–April 1, and the 7-day mean crosses the 61°F threshold around April 1. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline November 9

The window opens October 30 once water leaves the algae zone; the model deadline is November 9, a week ahead of the November 17 freeze normal.

Full closing guide

Where the water sits today

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 Lewisville water runs about 44°F at its winter floor and 86°F at its summer peak.

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

Estimated water temperature by month

Monthly averages of the site's water model run on Lewisville's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.

Site-model seasonal water estimates for an unheated in-ground pool near Grapevine Dam — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
45°47°53°61°68°78°83°86°81°72°60°51°

Warmest water typically June–September (peaking near 86°F); heaters and covers shift any month up.

Data: NOAA 1991–2020 climate normals via Grapevine Dam (7.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.