Pool season · Illinois
Champaign Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
This is the one-page view of Champaign'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 Champaign's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 19–May 10 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 Champaign pool calendar
Opening — target April 26
Open by April 26 — a two-week head start on the May 10 crossing keeps startup chemistry small and beats the local service rush.
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 24 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on Champaign'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 28° | 27° | 36° | 47° | 58° | 69° | 75° | 75° | 71° | 61° | 48° | 36° |
The curve peaks near 75°F — comfortable-water months here usually involve a heater or a solar cover.
Email me when Champaign hits the closing window
Data: NOAA 1991–2020 climate normals via Champaign 3s (2.7 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.