Pool season · Ohio
Dayton Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
This is the one-page view of Dayton'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 Dayton's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 16–May 7 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 11. Wherever the today marker sits, the nearest color change is your next appointment.
The Dayton pool calendar
Opening — target April 23
Target April 23; the practical window runs April 16–May 7, and the 7-day mean crosses the 61°F threshold around May 7. Cold-water starts are the cheap ones.
Closing — deadline October 11
The window opens October 1 once water leaves the algae zone; the model deadline is October 11, a week ahead of the October 25 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on Dayton'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 30° | 29° | 36° | 47° | 59° | 69° | 76° | 76° | 72° | 61° | 48° | 37° |
The curve peaks near 76°F — comfortable-water months here usually involve a heater or a solar cover.
Email me when Dayton hits the closing window
Data: NOAA 1991–2020 climate normals via Dayton Mcd (1.3 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.