PoolWindow

Pool season · Georgia

Alpharetta Pool Season: the Year on One Bar

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

One bar, one year, one Alpharetta 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 climateAlpharetta, GA — 135 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 Alpharetta's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the March 26–April 16 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 27. Wherever the today marker sits, the nearest color change is your next appointment.

The Alpharetta pool calendar

April 2open by
October 27close by
13580°F+ days
80°Fwater peak

Opening — target April 2

Open by April 2 — a two-week head start on the April 16 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline October 27

The window opens October 17 once water leaves the algae zone; the model deadline is October 27, a week ahead of the November 9 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 Alpharetta water runs about 42°F at its winter floor and 80°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 Alpharetta'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 Apr 2close Oct 2780°F peak42°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Atlanta Peachtree Airport — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
43°44°50°58°66°74°78°80°76°68°56°48°

Warmest water typically July–August (peaking near 80°F); heaters and covers shift any month up.

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

Alpharetta pool season FAQ

When should I open my pool in Alpharetta, GA?

The site model recommends opening by April 2 — about two weeks before Alpharetta'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 Alpharetta opening guide.

When should I close my pool in Alpharetta?

Winterize by October 27. The model holds the deadline a week ahead of Alpharetta's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Alpharetta closing guide.

How long is the swim season in Alpharetta?

Alpharetta averages 135 days a year with normal highs of 80°F or better — about 5 days later than the Georgia median. The Georgia season index ranks all 18 covered cities by the same metric.

How warm does pool water get in Alpharetta?

An unheated pool near Alpharetta typically peaks around 80°F in high summer and bottoms out near 42°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 Atlanta Peachtree Airport (13.6 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.