PoolWindow

Pool season · North Carolina

Durham Pool Season: the Year on One Bar

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

Durham'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 Durham's swim season; the hollow teal run before it (April 5 to April 26) is when to open; the hollow amber run after is when to close, with October 20 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Durham pool calendar

April 12open by
October 20close by
10580°F+ days
78°Fwater peak

Opening — target April 12

Open by April 12 — a two-week head start on the April 26 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline October 20

The window opens October 10 once water leaves the algae zone; the model deadline is October 20, a week ahead of the November 4 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 Durham water runs about 38°F at its winter floor and 78°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 Durham'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 Durham — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
40°39°45°54°63°70°77°77°73°65°53°45°

The curve peaks near 78°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via Durham (5.5 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.