Pool season · Indiana
Bloomington Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
One bar, one year, one Bloomington pool. The season bar below draws everything the model knows — opening window, prime season, closing window — against today's date, with the working details one click away on the opening and closing pages.
Reading it takes ten seconds: 52 dots, one per week. Solid teal is Bloomington's swim season; the hollow teal run before it (April 18 to May 9) is when to open; the hollow amber run after is when to close, with October 11 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Bloomington pool calendar
Opening — target April 25
Target April 25; the practical window runs April 18–May 9, and the 7-day mean crosses the 61°F threshold around May 9. Cold-water starts are the cheap ones.
Closing — deadline October 11
Hold the cover until October 1, then winterize by October 11, a week ahead of the October 26 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
This is Bloomington'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 30° | 30° | 38° | 48° | 59° | 68° | 74° | 75° | 71° | 61° | 49° | 38° |
The curve peaks near 75°F — comfortable-water months here usually involve a heater or a solar cover.
Email me when Bloomington hits the closing window
Data: NOAA 1991–2020 climate normals via Bloomington Indiana University (0.7 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.