Pool season · California
Upland Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
One bar, one year, one Upland 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.
The bar compresses Upland's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the March 4–March 25 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 28. Wherever the today marker sits, the nearest color change is your next appointment.
The Upland pool calendar
Opening — target March 11
Target March 11; the practical window runs March 4–March 25, and the 7-day mean crosses the 61°F threshold around March 25. Cold-water starts are the cheap ones.
Closing — deadline November 28
Hold the cover until November 18, then winterize by November 28, a week ahead of the December 30 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
Monthly averages of the site's water model run on Upland'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 56° | 56° | 59° | 62° | 66° | 70° | 77° | 80° | 80° | 74° | 66° | 58° |
Warmest water typically August–September (peaking near 80°F); heaters and covers shift any month up.
Email me when Upland hits the closing window
Data: NOAA 1991–2020 climate normals via Ontario International Airport (5.5 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.