PoolWindow

Pool season · North Carolina

Jacksonville Pool Season: the Year on One Bar

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

One bar, one year, one Jacksonville 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.

Courtyard swimming pool at dawn in a temperate climateJacksonville, NC — 138 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

The bar compresses Jacksonville's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the March 20–April 10 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 5. Wherever the today marker sits, the nearest color change is your next appointment.

The Jacksonville pool calendar

March 27open by
November 5close by
13880°F+ days
81°Fwater peak

Opening — target March 27

Target March 27; the practical window runs March 20–April 10, and the 7-day mean crosses the 61°F threshold around April 10. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline November 5

Hold the cover until October 26, then winterize by November 5, a week ahead of the November 16 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 Jacksonville water runs about 46°F at its winter floor and 81°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 Jacksonville's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.

30°40°50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Mar 27close Nov 581°F peak46°F floor
Site-model seasonal water estimates for an unheated in-ground pool near New River Mcaf — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
47°46°52°59°67°74°80°80°78°70°59°51°

Warmest water typically July–September (peaking near 81°F); heaters and covers shift any month up.

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

Jacksonville pool season FAQ

When should I open my pool in Jacksonville, NC?

Target March 27. That date backs off two weeks from the day Jacksonville's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Jacksonville opening guide.

When should I close my pool in Jacksonville?

The closing deadline is November 5 — late enough that the water has cooled out of the algae zone, early enough to beat Jacksonville's first-freeze normal by about a week. See the Jacksonville closing guide for the winterizing steps.

How long is the swim season in Jacksonville?

Jacksonville averages 138 days a year with normal highs of 80°F or better — about 8 days earlier than the North Carolina median. The North Carolina season index ranks all 17 covered cities by the same metric.

How warm does pool water get in Jacksonville?

An unheated pool near Jacksonville typically peaks around 81°F in high summer and bottoms out near 46°F in winter, spending roughly 2 months at or above the 78°F comfort line most swimmers prefer. 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 New River Mcaf (2.1 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.