Pool season · Arizona
San Tan Valley Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
San Tan Valley'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.
San Tan Valley, AZ — 219 swim days a yearEach dot on the bar is one week of San Tan Valley's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (February 18–March 11), solid teal is swim season, and hollow amber is the closing window ending November 23. The black marker is today — its position against the colors is the entire executive summary.
The San Tan Valley pool calendar
Opening — target February 25
Target February 25; the practical window runs February 18–March 11, and the 7-day mean crosses the 61°F threshold around March 11. Cold-water starts are the cheap ones.
Closing — deadline November 23
The window opens November 13 once water leaves the algae zone; the model deadline is November 23, a week ahead of the December 11 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on San Tan Valley's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 52° | 55° | 59° | 66° | 73° | 83° | 90° | 91° | 88° | 79° | 66° | 55° |
Warmest water typically June–October (peaking near 92°F); heaters and covers shift any month up.
Every station tells its own story: compare this curve with Queen Creek's pool season and Scottsdale's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Arizona season index.
San Tan Valley pool season FAQ
When should I open my pool in San Tan Valley, AZ?
Target February 25. That date backs off two weeks from the day San Tan Valley's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the San Tan Valley opening guide.
When should I close my pool in San Tan Valley?
The closing deadline is November 23 — late enough that the water has cooled out of the algae zone, early enough to beat San Tan Valley's first-freeze normal by about a week. See the San Tan Valley closing guide for the winterizing steps.
How long is the swim season in San Tan Valley?
San Tan Valley averages 219 days a year with normal highs of 80°F or better — right on the statewide median. The Arizona season index ranks all 20 covered cities by the same metric.
How warm does pool water get in San Tan Valley?
An unheated pool near San Tan Valley typically peaks around 92°F in high summer and bottoms out near 51°F in winter, spending roughly 5 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 San Tan Valley hits the closing window
Data: NOAA 1991–2020 climate normals via Chandler Heights (7.1 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.