Pool season · Wisconsin
La Crosse Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
La Crosse'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.
La Crosse, WI — 0 swim days a yearReading it takes ten seconds: 52 dots, one per week. Solid teal is La Crosse's swim season; the hollow teal run before it (May 6 to May 27) is when to open; the hollow amber run after is when to close, with September 26 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The La Crosse pool calendar
Opening — target May 13
Target May 13; the practical window runs May 6–May 27, and the 7-day mean crosses the 61°F threshold around May 27. Cold-water starts are the cheap ones.
Closing — deadline September 26
The window opens September 16 once water leaves the algae zone; the model deadline is September 26, a week ahead of the October 13 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on La Crosse'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 18° | 17° | 27° | 40° | 52° | 63° | 70° | 70° | 66° | 55° | 41° | 28° |
The curve peaks near 71°F — comfortable-water months here usually involve a heater or a solar cover.
Every station tells its own story: compare this curve with Kenosha's pool season and Madison's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Wisconsin season index.
La Crosse pool season FAQ
When should I open my pool in La Crosse, WI?
Open by May 13 — the model places La Crosse's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The La Crosse opening guide has the 12-step sequence.
When should I close my pool in La Crosse?
Close by September 26: cool water keeps its winter chemistry, but freeze damage is the hard stop. The La Crosse closing guide sequences the work backward from that date.
How long is the swim season in La Crosse?
La Crosse averages 0 days a year with normal highs of 80°F or better — right on the statewide median. The Wisconsin season index ranks all 11 covered cities by the same metric.
How warm does pool water get in La Crosse?
An unheated pool near La Crosse typically peaks around 71°F in high summer and bottoms out near 16°F in winter, never quite reaching the 78°F comfort line without a heater or solar cover. The month-by-month curve above shows the whole cycle; the methodology page explains the ±5°F error bars.
Email me when La Crosse hits the closing window
Data: NOAA 1991–2020 climate normals via La Crosse Wfo (1.7 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.