PoolWindow

Pool season · Oregon

Portland Pool Season: the Year on One Bar

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

Portland'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

Reading it takes ten seconds: 52 dots, one per week. Solid teal is Portland's swim season; the hollow teal run before it (May 11 to June 1) is when to open; the hollow amber run after is when to close, with October 10 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Portland pool calendar

May 18open by
October 10close by
4080°F+ days
70°Fwater peak

Opening — target May 18

Open by May 18 — a two-week head start on the June 1 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline October 10

Hold the cover until September 30, then winterize by October 10, a week ahead of the December 1 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 Portland water runs about 41°F at its winter floor and 70°F at its summer peak.

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

Estimated water temperature by month

Monthly averages of the site's water model run on Portland's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.

Site-model seasonal water estimates for an unheated in-ground pool near Portland Kgw-tv — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
41°43°47°50°56°61°66°70°68°60°51°44°

The curve peaks near 70°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via Portland Kgw-tv (2.3 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.