PoolWindow

Pool season · Virginia

Portsmouth Pool Season: the Year on One Bar

Last updated: July 15, 2026 · dates · water temp

This is the one-page view of Portsmouth's pool year: both model windows, the estimated water-temperature curve, and today's live position on the season bar. The detailed checklists live on the opening and closing guides; this page is the calendar you check between them.

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 Portsmouth's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the March 31–April 21 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 28. Wherever the today marker sits, the nearest color change is your next appointment.

The Portsmouth pool calendar

April 7open by
October 28close by
10580°F+ days
79°Fwater peak

Opening — target April 7

Open by April 7 — a two-week head start on the April 21 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline October 28

Hold the cover until October 18, then winterize by October 28, 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 Portsmouth 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

This is Portsmouth'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.

Site-model seasonal water estimates for an unheated in-ground pool near Norfolk S — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
42°41°46°55°64°71°78°79°75°67°56°47°

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

Data: NOAA 1991–2020 climate normals via Norfolk S (7.1 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.