PoolWindow

Pool season · California

Chino Pool Season: the Year on One Bar

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

This is the one-page view of Chino'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

Reading it takes ten seconds: 52 dots, one per week. Solid teal is Chino's swim season; the hollow teal run before it (March 14 to April 4) is when to open; the hollow amber run after is when to close, with November 24 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Chino pool calendar

March 21open by
November 24close by
18380°F+ days
80°Fwater peak

Opening — target March 21

Target March 21; the practical window runs March 14–April 4, and the 7-day mean crosses the 61°F threshold around April 4. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline November 24

Hold the cover until November 14, then winterize by November 24, a week ahead of the December 19 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 Chino water runs about 55°F at its winter floor and 80°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 Chino'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 Chino Airport — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
55°56°58°61°66°70°76°79°79°73°65°57°

Warmest water typically August–September (peaking near 80°F); heaters and covers shift any month up.

Data: NOAA 1991–2020 climate normals via Chino Airport (1.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.