PoolWindow

Pool season · California

San Jose Pool Season: the Year on One Bar

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

San Jose's whole pool calendar, condensed: when the water warms, when it cools, and where today falls between those edges. Use the opening guide and closing guide for the step-by-step work; keep this page for the dates.

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 San Jose's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 5–April 26 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 7. Wherever the today marker sits, the nearest color change is your next appointment.

The San Jose pool calendar

April 12open by
November 7close by
10480°F+ days
71°Fwater peak

Opening — target April 12

Open by April 12 — a two-week head start on the April 26 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline November 7

Hold the cover until October 28, then winterize by November 7, a week ahead of the December 25 freeze normal. Late and cold beats early and warm.

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 San Jose water runs about 50°F at its winter floor and 71°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 San Jose'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 San Jose — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
50°53°56°59°62°67°70°71°71°67°60°53°

The curve peaks near 71°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via San Jose (4.5 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.