PoolWindow

Pool season · Virginia

Williamsburg Pool Season: the Year on One Bar

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

One bar, one year, one Williamsburg 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 climateWilliamsburg, VA — 111 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 Williamsburg's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (April 2–April 23), solid teal is swim season, and hollow amber is the closing window ending October 26. The black marker is today — its position against the colors is the entire executive summary.

The Williamsburg pool calendar

April 9open by
October 26close by
11180°F+ days
79°Fwater peak

Opening — target April 9

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

Full opening guide

Closing — deadline October 26

Hold the cover until October 16, then winterize by October 26, a week ahead of the November 10 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 Williamsburg water runs about 40°F at its winter floor and 79°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 Williamsburg'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 9close Oct 2679°F peak40°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Williamsburg 2 N — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
41°40°46°55°64°71°78°79°75°66°56°47°

Warmest water typically July–August (peaking near 79°F); heaters and covers shift any month up.

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

Williamsburg pool season FAQ

When should I open my pool in Williamsburg, VA?

Target April 9. That date backs off two weeks from the day Williamsburg's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Williamsburg opening guide.

When should I close my pool in Williamsburg?

The closing deadline is October 26 — late enough that the water has cooled out of the algae zone, early enough to beat Williamsburg's first-freeze normal by about a week. See the Williamsburg closing guide for the winterizing steps.

How long is the swim season in Williamsburg?

Williamsburg averages 111 days a year with normal highs of 80°F or better — right on the statewide median. The Virginia season index ranks all 16 covered cities by the same metric.

How warm does pool water get in Williamsburg?

An unheated pool near Williamsburg typically peaks around 79°F in high summer and bottoms out near 40°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 Williamsburg 2 N (2.2 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.