Pool season · Pennsylvania
Bethlehem Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
Bethlehem'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.
The bar compresses Bethlehem's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 22–May 13 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 9. Wherever the today marker sits, the nearest color change is your next appointment.
The Bethlehem pool calendar
Opening — target April 29
Open by April 29 — a two-week head start on the May 13 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline October 9
Hold the cover until September 29, then winterize by October 9, a week ahead of the October 24 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
This is Bethlehem'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 32° | 30° | 37° | 47° | 58° | 67° | 74° | 75° | 70° | 60° | 49° | 39° |
The curve peaks near 76°F — comfortable-water months here usually involve a heater or a solar cover.
Email me when Bethlehem hits the closing window
Data: NOAA 1991–2020 climate normals via Allentown International Airport (4.6 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.