PoolWindow

Pool season · California

Merced Pool Season: the Year on One Bar

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

This is the one-page view of Merced'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.

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

off-season opening window swim season closing window

The bar compresses Merced's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 3–April 24 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 2. Wherever the today marker sits, the nearest color change is your next appointment.

The Merced pool calendar

April 10open by
November 2close by
15880°F+ days
79°Fwater peak

Opening — target April 10

Target April 10; the practical window runs April 3–April 24, and the 7-day mean crosses the 61°F threshold around April 24. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline November 2

The window opens October 23 once water leaves the algae zone; the model deadline is November 2, a week ahead of the November 24 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 Merced water runs about 45°F at its winter floor and 79°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 Merced'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 Merced — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
45°48°53°57°63°70°77°78°75°68°58°48°

Warmest water typically August–August (peaking near 79°F); heaters and covers shift any month up.

Data: NOAA 1991–2020 climate normals via Merced (2.4 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.