PoolWindow

Pool season · Washington

Auburn Pool Season: the Year on One Bar

Last updated: July 25, 2026 · dates · water temp

This is the one-page view of Auburn's pool year: both model windows, the estimated water-temperature curve, and today's live position on the season bar. The detailed checklists live on the opening and closing guides; this page is the calendar you check between them.

Cool blue pool in a short-season northern climateAuburn, WA — 0 swim days a year
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 Auburn's swim season; the hollow teal run before it (May 14 to June 4) is when to open; the hollow amber run after is when to close, with October 1 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Auburn pool calendar

May 21open by
October 1close by
080°F+ days
69°Fwater peak

Opening — target May 21

Target May 21; the practical window runs May 14–June 4, and the 7-day mean crosses the 61°F threshold around June 4. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline October 1

The window opens September 21 once water leaves the algae zone; the model deadline is October 1, a week ahead of the November 10 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 Auburn water runs about 41°F at its winter floor and 69°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 Auburn'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.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen May 21close Oct 169°F peak41°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Kent — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
41°43°46°50°56°61°66°69°65°58°49°43°

The curve peaks near 69°F — comfortable-water months here usually involve a heater or a solar cover.

Every station tells its own story: compare this curve with Yakima's pool season and Bellevue's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Washington season index.

Auburn pool season FAQ

When should I open my pool in Auburn, WA?

Target May 21. That date backs off two weeks from the day Auburn's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Auburn opening guide.

When should I close my pool in Auburn?

The closing deadline is October 1 — late enough that the water has cooled out of the algae zone, early enough to beat Auburn's first-freeze normal by about a week. See the Auburn closing guide for the winterizing steps.

How long is the swim season in Auburn?

Auburn averages 0 days a year with normal highs of 80°F or better — right on the statewide median. The Washington season index ranks all 21 covered cities by the same metric.

How warm does pool water get in Auburn?

An unheated pool near Auburn typically peaks around 69°F in high summer and bottoms out near 41°F in winter, never quite reaching the 78°F comfort line without a heater or solar cover. The month-by-month curve above shows the whole cycle; the methodology page explains the ±5°F error bars.

Data: NOAA 1991–2020 climate normals via Kent (8.0 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.