Pool season · Texas
Harlingen Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
This is the one-page view of Harlingen's pool year: both model windows, the estimated water-temperature curve, and today's live position on the season bar. The detailed checklists live on the opening and closing guides; this page is the calendar you check between them.
Reading it takes ten seconds: 52 dots, one per week. Solid teal is Harlingen's swim season; the hollow teal run before it (January 1 to January 15) is when to open; the hollow amber run after is when to close, with December 27 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Harlingen pool calendar
Opening — target January 1
Target January 1; the practical window runs January 1–January 15, and the 7-day mean crosses the 61°F threshold around January 15. Cold-water starts are the cheap ones.
Closing — deadline December 27
The window opens December 29 once water leaves the algae zone; the model deadline is December 27, a week ahead of the January 3 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on Harlingen's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 61° | 63° | 68° | 74° | 79° | 84° | 86° | 87° | 86° | 81° | 73° | 66° |
Warmest water typically May–October (peaking near 88°F); heaters and covers shift any month up.
Email me when Harlingen hits the closing window
Data: NOAA 1991–2020 climate normals via Harlingen (1.7 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.