Pool season · Michigan
Rochester Hills Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
This is the one-page view of Rochester Hills'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.
Rochester Hills, MI — 63 swim days a yearEach dot on the bar is one week of Rochester Hills's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (April 30–May 21), solid teal is swim season, and hollow amber is the closing window ending October 3. The black marker is today — its position against the colors is the entire executive summary.
The Rochester Hills pool calendar
Opening — target May 7
Target May 7; the practical window runs April 30–May 21, and the 7-day mean crosses the 61°F threshold around May 21. Cold-water starts are the cheap ones.
Closing — deadline October 3
The window opens September 23 once water leaves the algae zone; the model deadline is October 3, a week ahead of the October 22 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on Rochester Hills'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 27° | 24° | 31° | 42° | 54° | 65° | 71° | 72° | 68° | 58° | 45° | 35° |
The curve peaks near 73°F — comfortable-water months here usually involve a heater or a solar cover.
Every station tells its own story: compare this curve with Port Huron's pool season and Saginaw's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Michigan season index.
Rochester Hills pool season FAQ
When should I open my pool in Rochester Hills, MI?
Target May 7. That date backs off two weeks from the day Rochester Hills's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Rochester Hills opening guide.
When should I close my pool in Rochester Hills?
The closing deadline is October 3 — late enough that the water has cooled out of the algae zone, early enough to beat Rochester Hills's first-freeze normal by about a week. See the Rochester Hills closing guide for the winterizing steps.
How long is the swim season in Rochester Hills?
Rochester Hills averages 63 days a year with normal highs of 80°F or better — right on the statewide median. The Michigan season index ranks all 23 covered cities by the same metric.
How warm does pool water get in Rochester Hills?
An unheated pool near Rochester Hills typically peaks around 73°F in high summer and bottoms out near 24°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 Rochester Hills hits the closing window
Data: NOAA 1991–2020 climate normals via Pontiac Wwtp (5.3 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.