PoolWindow

Pool season · California

Alhambra Pool Season: the Year on One Bar

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

Alhambra'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 Alhambra's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the February 25–March 18 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 30. Wherever the today marker sits, the nearest color change is your next appointment.

The Alhambra pool calendar

March 4open by
November 30close by
13080°F+ days
77°Fwater peak

Opening — target March 4

Open by March 4 — a two-week head start on the March 18 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline November 30

Hold the cover until November 20, then winterize by November 30, a week ahead of the January 2 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 Alhambra water runs about 56°F at its winter floor and 77°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 Alhambra'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 Gabriel Fire Dept — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
57°57°59°62°65°69°74°76°77°72°66°58°

The curve peaks near 77°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via San Gabriel Fire Dept (2.0 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.