Pool season · Massachusetts
Worcester Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
One bar, one year, one Worcester 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 Worcester's swim season; the hollow teal run before it (May 12 to June 2) is when to open; the hollow amber run after is when to close, with September 28 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Worcester pool calendar
Opening — target May 19
Target May 19; the practical window runs May 12–June 2, and the 7-day mean crosses the 61°F threshold around June 2. Cold-water starts are the cheap ones.
Closing — deadline September 28
Hold the cover until September 18, then winterize by September 28, a week ahead of the October 21 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
Monthly averages of the site's water model run on Worcester'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° | 25° | 31° | 41° | 52° | 61° | 69° | 70° | 66° | 56° | 45° | 35° |
The curve peaks near 71°F — comfortable-water months here usually involve a heater or a solar cover.
Email me when Worcester hits the closing window
Data: NOAA 1991–2020 climate normals via Worcester Regional Airport (3.4 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.