PoolWindow

Pool season · Alabama

Birmingham Pool Season: the Year on One Bar

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

One bar, one year, one Birmingham 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.

Resort pool at dusk in a hot, long-season climateBirmingham, AL — 152 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

Reading it takes ten seconds: 52 dots, one per week. Solid teal is Birmingham's swim season; the hollow teal run before it (March 16 to April 6) 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 Birmingham pool calendar

March 23open by
November 4close by
15280°F+ days
82°Fwater peak

Opening — target March 23

Open by March 23 — a two-week head start on the April 6 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline November 4

The window opens October 25 once water leaves the algae zone; the model deadline is November 4, a week ahead of the November 11 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 Birmingham 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

Monthly averages of the site's water model run on Birmingham'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 23close Nov 482°F peak45°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Birmingham Airport — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
45°46°53°60°68°76°80°82°79°70°59°50°

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

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

Birmingham pool season FAQ

When should I open my pool in Birmingham, AL?

The site model recommends opening by March 23 — about two weeks before Birmingham's 7-day mean temperature crosses 61°F, while the water is still too cold for algae. The step-by-step sequence is in the Birmingham opening guide.

When should I close my pool in Birmingham?

Winterize by November 4. The model holds the deadline a week ahead of Birmingham's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Birmingham closing guide.

How long is the swim season in Birmingham?

Birmingham averages 152 days a year with normal highs of 80°F or better — right on the statewide median. The Alabama season index ranks all 10 covered cities by the same metric.

How warm does pool water get in Birmingham?

An unheated pool near Birmingham typically peaks around 82°F in high summer and bottoms out near 45°F in winter, spending roughly 3 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 Birmingham Airport (4.0 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.