Pool season · Wisconsin
Sheboygan Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
One bar, one year, one Sheboygan 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.
Sheboygan, WI — 49 swim days a yearEach dot on the bar is one week of Sheboygan's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (May 15–June 5), solid teal is swim season, and hollow amber is the closing window ending October 2. The black marker is today — its position against the colors is the entire executive summary.
The Sheboygan pool calendar
Opening — target May 22
Target May 22; the practical window runs May 15–June 5, and the 7-day mean crosses the 61°F threshold around June 5. Cold-water starts are the cheap ones.
Closing — deadline October 2
Hold the cover until September 22, then winterize by October 2, a week ahead of the October 23 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
This is Sheboygan'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 25° | 23° | 30° | 39° | 50° | 60° | 70° | 72° | 68° | 57° | 44° | 33° |
The curve peaks near 72°F — comfortable-water months here usually involve a heater or a solar cover.
Every station tells its own story: compare this curve with Racine's pool season and Wausau's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Wisconsin season index.
Sheboygan pool season FAQ
When should I open my pool in Sheboygan, WI?
The site model recommends opening by May 22 — about two weeks before Sheboygan's 7-day mean temperature crosses 61°F, while the water is still too cold for algae. The step-by-step sequence is in the Sheboygan opening guide.
When should I close my pool in Sheboygan?
Winterize by October 2. The model holds the deadline a week ahead of Sheboygan's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Sheboygan closing guide.
How long is the swim season in Sheboygan?
Sheboygan averages 49 days a year with normal highs of 80°F or better — about 9 days later than the Wisconsin median. The Wisconsin season index ranks all 11 covered cities by the same metric.
How warm does pool water get in Sheboygan?
An unheated pool near Sheboygan typically peaks around 72°F in high summer and bottoms out near 22°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 Sheboygan hits the closing window
Data: NOAA 1991–2020 climate normals via Sheboygan (1.0 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.