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Pool season · Florida

Jacksonville Pool Season: the Year on One Bar

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

Jacksonville'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.

Resort pool at dusk in a hot, long-season climateJacksonville, FL — 193 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

Each dot on the bar is one week of Jacksonville's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (February 2–February 23), solid teal is swim season, and hollow amber is the closing window ending December 12. The black marker is today — its position against the colors is the entire executive summary.

The Jacksonville pool calendar

February 9open by
December 12close by
19380°F+ days
84°Fwater peak

Opening — target February 9

Target February 9; the practical window runs February 2–February 23, and the 7-day mean crosses the 61°F threshold around February 23. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline December 12

Hold the cover until December 2, then winterize by December 12, a week ahead of the January 5 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 56°F at its winter floor and 84°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 Jacksonville'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.

50°60°70°80°90°100°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Feb 9close Dec 1284°F peak56°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Jacksonville NAS — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
57°58°62°68°75°80°83°84°82°78°69°61°

Warmest water typically June–October (peaking near 84°F); heaters and covers shift any month up.

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

Jacksonville pool season FAQ

When should I open my pool in Jacksonville, FL?

Open by February 9 — the model places Jacksonville's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Jacksonville opening guide has the 12-step sequence.

When should I close my pool in Jacksonville?

Close by December 12: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Jacksonville closing guide sequences the work backward from that date.

How long is the swim season in Jacksonville?

Jacksonville averages 193 days a year with normal highs of 80°F or better — about 16 days later than the Florida median. The Florida season index ranks all 64 covered cities by the same metric.

How warm does pool water get in Jacksonville?

An unheated pool near Jacksonville typically peaks around 84°F in high summer and bottoms out near 56°F in winter, spending roughly 4 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 Jacksonville NAS (6.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.