PoolWindow

Pool season · Minnesota

Plymouth Pool Season: the Year on One Bar

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

Plymouth'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 Plymouth's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the May 3–May 24 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends September 28. Wherever the today marker sits, the nearest color change is your next appointment.

The Plymouth pool calendar

May 10open by
September 28close by
5580°F+ days
73°Fwater peak

Opening — target May 10

Target May 10; the practical window runs May 3–May 24, and the 7-day mean crosses the 61°F threshold around May 24. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline September 28

Hold the cover until September 18, then winterize by September 28, a week ahead of the October 12 freeze normal. Late and cold beats early and warm.

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 Plymouth water runs about 15°F at its winter floor and 73°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 Plymouth'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 New Hope — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
17°16°26°40°53°64°72°72°67°55°40°27°

The curve peaks near 73°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via New Hope (4.1 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.