Pool season · California
Chino Pool Season: the Year on One Bar
Last updated: July 25, 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.
Chino, CA — 183 swim days a yearReading 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
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.
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.
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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 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.
Every station tells its own story: compare this curve with Chico's pool season and Chino Hills's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the California season index.
Chino pool season FAQ
When should I open my pool in Chino, CA?
The site model recommends opening by March 21 — about two weeks before Chino's 7-day mean temperature crosses 61°F, while the water is still too cold for algae. The step-by-step sequence is in the Chino opening guide.
When should I close my pool in Chino?
Winterize by November 24. The model holds the deadline a week ahead of Chino's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Chino closing guide.
How long is the swim season in Chino?
Chino averages 183 days a year with normal highs of 80°F or better — about 11 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 Chino?
An unheated pool near Chino typically peaks around 80°F in high summer and bottoms out near 55°F in winter, spending roughly 2 months at or above the 78°F comfort line most swimmers prefer. The month-by-month curve above shows the whole cycle; the methodology page explains the ±5°F error bars.
Email me when Chino hits the closing window
Data: NOAA 1991–2020 climate normals via Chino Airport (1.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.