PoolWindow

Pool season · Ohio

Columbus Pool Season: the Year on One Bar

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

One bar, one year, one Columbus pool. The season bar below draws everything the model knows — opening window, prime season, closing window — against today's date, with the working details one click away on the opening and closing pages.

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

off-season opening window swim season closing window

Each dot on the bar is one week of Columbus's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (April 20–May 11), solid teal is swim season, and hollow amber is the closing window ending October 10. The black marker is today — its position against the colors is the entire executive summary.

The Columbus pool calendar

April 27open by
October 10close by
9780°F+ days
75°Fwater peak

Opening — target April 27

Target April 27; the practical window runs April 20–May 11, and the 7-day mean crosses the 61°F threshold around May 11. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline October 10

Hold the cover until September 30, then winterize by October 10, a week ahead of the October 24 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 Columbus water runs about 28°F at its winter floor and 75°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 Columbus'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 Columbus Wcmh — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
30°29°36°48°58°68°74°74°70°61°48°38°

The curve peaks near 75°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via Columbus Wcmh (3.5 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.