PoolWindow

Pool season · California

Downey Pool Season: the Year on One Bar

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

This is the one-page view of Downey'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

Each dot on the bar is one week of Downey'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 9–March 30), solid teal is swim season, and hollow amber is the closing window ending November 29. The black marker is today — its position against the colors is the entire executive summary.

The Downey pool calendar

March 16open by
November 29close by
8980°F+ days
74°Fwater peak

Opening — target March 16

Target March 16; the practical window runs March 9–March 30, and the 7-day mean crosses the 61°F threshold around March 30. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline November 29

Hold the cover until November 19, then winterize by November 29, 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 Downey water runs about 56°F at its winter floor and 74°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 Downey'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 Long Beach Daugherty Field — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
57°57°59°61°64°67°71°74°74°71°65°58°

The curve peaks near 74°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via Long Beach Daugherty Field (8.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.