PoolWindow

Pool season · California

Santa Clara Pool Season: the Year on One Bar

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

Santa Clara'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 Santa Clara's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 12–May 3 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 8. Wherever the today marker sits, the nearest color change is your next appointment.

The Santa Clara pool calendar

April 19open by
November 8close by
9480°F+ days
70°Fwater peak

Opening — target April 19

Open by April 19 — a two-week head start on the May 3 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline November 8

Hold the cover until October 29, then winterize by November 8, a week ahead of the December 22 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 Santa Clara water runs about 50°F at its winter floor and 70°F at its summer peak.

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

Estimated water temperature by month

This is Santa Clara's typical-year water curve: the same EWMA model as the live widget, run on the 1991–2020 normals instead of this week's weather.

Site-model seasonal water estimates for an unheated in-ground pool near San Jose — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
50°52°55°57°61°66°69°70°70°67°60°52°

The curve peaks near 70°F — comfortable-water months here usually involve a heater or a solar cover.

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