PoolWindow

Pool season · California

Los Angeles Pool Season: the Year on One Bar

Last updated: July 25, 2026 · dates · water temp

Los Angeles'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.

Cool blue pool in a short-season northern climateLos Angeles, CA — 0 swim days a year
J F M A M J J A S O N D today (build date)

off-season opening window swim season closing window

Each dot on the bar is one week of Los Angeles's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (March 15–April 5), solid teal is swim season, and hollow amber is the closing window ending December 8. The black marker is today — its position against the colors is the entire executive summary.

The Los Angeles pool calendar

March 22open by
December 8close by
080°F+ days
71°Fwater peak

Opening — target March 22

Target March 22; the practical window runs March 15–April 5, and the 7-day mean crosses the 61°F threshold around April 5. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline December 8

Hold the cover until November 28, then winterize by December 8, a week ahead of the December 26 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 Los Angeles water runs about 59°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 Los Angeles's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.

50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Mar 22close Dec 871°F peak59°F floor
Site-model seasonal water estimates for an unheated in-ground pool near U C L A — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
60°59°59°61°63°64°68°70°71°69°66°61°

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

Every station tells its own story: compare this curve with Long Beach's pool season and Madera's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the California season index.

Los Angeles pool season FAQ

When should I open my pool in Los Angeles, CA?

Open by March 22 — the model places Los Angeles's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Los Angeles opening guide has the 12-step sequence.

When should I close my pool in Los Angeles?

Close by December 8: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Los Angeles closing guide sequences the work backward from that date.

How long is the swim season in Los Angeles?

Los Angeles averages 0 days a year with normal highs of 80°F or better — about 10 days earlier than the California median. The California season index ranks all 147 covered cities by the same metric.

How warm does pool water get in Los Angeles?

An unheated pool near Los Angeles typically peaks around 71°F in high summer and bottoms out near 59°F in winter, never quite reaching the 78°F comfort line without a heater or solar cover. The month-by-month curve above shows the whole cycle; the methodology page explains the ±5°F error bars.

Data: NOAA 1991–2020 climate normals via U C L A (3.7 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.