Pool season · State index
Oregon Pool Season 2026: Opening & Closing Dates by City
Last updated: July 25, 2026 · 8 cities covered
Both halves of the pool year for all 8 covered Oregon cities. The median calendar runs May 23 to October 5. Every row links to a one-page season overview with the live water-temperature model; the opening and closing hubs carry the full checklists.
Oregon: a moderate-season pool state| City | Open by | Close by | 80°F+ days |
|---|---|---|---|
| Beaverton | May 23 | Oct 5 | 59 |
| Bend | Jun 14 | Sep 13 | 60 |
| Eugene | Jun 4 | Oct 3 | 71 |
| Gresham | May 15 | Oct 7 | 58 |
| Hillsboro | Jun 3 | Sep 30 | 58 |
| Medford | May 4 | Oct 14 | 109 |
| Portland | May 18 | Oct 10 | 40 |
| Salem | May 24 | Oct 6 | 67 |
What the columns mean
"Open by" is the recommended spring date — two weeks before the city's 7-day mean temperature crosses 61°F, the model's proxy for water approaching the 65°F algae-growth zone. "Close by" is the fall deadline — ten days after the water leaves that zone, capped a week ahead of the local 50% first-freeze date. "80°F+ days" counts days whose normal high reaches 80°F: the length of the true warm-swim season, and the fairest single number for comparing Oregon cities against each other.
Every figure comes from each city's own NOAA 1991–2020 normals station (named in its guide's footer), so neighboring cities can legitimately differ by a few days. The season overview linked from each row adds the live water-temperature model and the full-year season bar; the state hubs above carry the step-by-step checklists.
Swim-season length across Oregon
The fairest way to compare Oregon cities is the number of days with 80°F+ normal highs — the practical warm-swim season. Every bar links to that city's one-page season overview with the live water model.
Oregon pool climate at a glance
West of the Cascades, cool wet springs delay warm-ups until reliably dry July and August weather arrives, while high-desert eastern Oregon sees hotter days but colder nights. In model terms that makes Oregon a moderate-season state. The spread shows up clearly on the local pages: compare Medford's pool season with Beaverton's and the difference is measured in weeks, not days. Neighbors in the index run on their own normals too — see Oklahoma and Pennsylvania for the adjacent calendars.
Oregon pool season FAQ
When do pools open in Oregon?
Model openings in Oregon run from May 4 in Medford to June 14 in Bend, with the statewide median on May 24. Each date is two weeks before that city's 7-day mean temperature crosses 61°F — early enough to start up in algae-cold water.
When should you close a pool in Oregon?
The median Oregon closing deadline is October 6, and every city's own deadline is capped a week ahead of its NOAA 50% first-freeze date. Closing late and cold beats closing early and warm — cool water holds its winter chemistry far better.
Which Oregon city has the longest swim season?
Medford leads with 109 days of 80°F+ highs per year, while Portland brings up the rear at 40 days. The chart above ranks every covered city by the same metric.