Pool season · California
Pittsburg Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
Pittsburg'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.
Pittsburg, CA — 142 swim days a yearReading it takes ten seconds: 52 dots, one per week. Solid teal is Pittsburg's swim season; the hollow teal run before it (March 27 to April 17) is when to open; the hollow amber run after is when to close, with November 10 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Pittsburg pool calendar
Opening — target April 3
Target April 3; the practical window runs March 27–April 17, and the 7-day mean crosses the 61°F threshold around April 17. Cold-water starts are the cheap ones.
Closing — deadline November 10
The window opens October 31 once water leaves the algae zone; the model deadline is November 10, a week ahead of the December 19 freeze normal.
Estimated water temperature by month
This is Pittsburg'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 47° | 50° | 55° | 59° | 64° | 70° | 75° | 76° | 74° | 70° | 60° | 51° |
The curve peaks near 76°F — comfortable-water months here usually involve a heater or a solar cover.
Every station tells its own story: compare this curve with Perris's pool season and Pleasanton's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the California season index.
Pittsburg pool season FAQ
When should I open my pool in Pittsburg, CA?
Open by April 3 — the model places Pittsburg's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Pittsburg opening guide has the 12-step sequence.
When should I close my pool in Pittsburg?
Close by November 10: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Pittsburg closing guide sequences the work backward from that date.
How long is the swim season in Pittsburg?
Pittsburg averages 142 days a year with normal highs of 80°F or better — right on the statewide median. The California season index ranks all 147 covered cities by the same metric.
How warm does pool water get in Pittsburg?
An unheated pool near Pittsburg typically peaks around 76°F in high summer and bottoms out near 47°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.
Email me when Pittsburg hits the closing window
Data: NOAA 1991–2020 climate normals via Antioch Pumping Plt #3 (8.2 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.