PoolWindow

Pool season · Minnesota

Rochester Pool Season: the Year on One Bar

Last updated: July 15, 2026 · dates · water temp

Rochester'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.

J F M A M J J A S O N D today (build date)

off-season opening window swim season closing window

The bar compresses Rochester's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the May 4–May 25 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends September 26. Wherever the today marker sits, the nearest color change is your next appointment.

The Rochester pool calendar

May 11open by
September 26close by
2880°F+ days
71°Fwater peak

Opening — target May 11

Target May 11; the practical window runs May 4–May 25, and the 7-day mean crosses the 61°F threshold around May 25. Cold-water starts are the cheap ones.

Full opening guide

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 6 freeze normal.

Full closing guide

Where the water sits today

SEASONAL VIEW

Estimated unheated pool water temp (site model, ±5°F). The live estimate loads in your browser from Open-Meteo air temperatures; in a typical year Rochester water runs about 15°F at its winter floor and 71°F at its summer peak.

40 45 50 55 60 65 70 75 80 85 58 open 65 algae

Estimated water temperature by month

This is Rochester'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.

Site-model seasonal water estimates for an unheated in-ground pool near Rochester International Airport — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
17°16°26°40°52°64°70°70°65°55°40°27°

The curve peaks near 71°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via Rochester International Airport (7.7 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.