PoolWindow

Pool season · South Carolina

Columbia Pool Season: the Year on One Bar

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

Columbia'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 Columbia's swim season; the hollow teal run before it (March 18 to April 8) is when to open; the hollow amber run after is when to close, with November 4 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Columbia pool calendar

March 25open by
November 4close by
15980°F+ days
82°Fwater peak

Opening — target March 25

Open by March 25 — a two-week head start on the April 8 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline November 4

Hold the cover until October 25, then winterize by November 4, a week ahead of the November 15 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 Columbia water runs about 45°F at its winter floor and 82°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 Columbia'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 Sandhill Rsch - Elgin — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
46°46°52°59°68°75°81°81°78°70°59°50°

Warmest water typically July–September (peaking near 82°F); heaters and covers shift any month up.

Data: NOAA 1991–2020 climate normals via Sandhill Rsch - Elgin (6.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.