Pool season · Arizona
Surprise Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
This is the one-page view of Surprise'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.
The bar compresses Surprise's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the February 27–March 20 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 22. Wherever the today marker sits, the nearest color change is your next appointment.
The Surprise pool calendar
Opening — target March 6
Open by March 6 — a two-week head start on the March 20 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline November 22
The window opens November 12 once water leaves the algae zone; the model deadline is November 22, a week ahead of the December 11 freeze normal.
Estimated water temperature by month
This is Surprise'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 52° | 53° | 58° | 63° | 71° | 81° | 89° | 91° | 88° | 78° | 66° | 54° |
Warmest water typically June–October (peaking near 91°F); heaters and covers shift any month up.
Email me when Surprise hits the closing window
Data: NOAA 1991–2020 climate normals via Wittmann 1se (7.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.