Pool season · Virginia
Arlington Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
This is the one-page view of Arlington'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.
Reading it takes ten seconds: 52 dots, one per week. Solid teal is Arlington's swim season; the hollow teal run before it (April 3 to April 24) is when to open; the hollow amber run after is when to close, with October 25 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Arlington pool calendar
Opening — target April 10
Open by April 10 — a two-week head start on the April 24 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline October 25
The window opens October 15 once water leaves the algae zone; the model deadline is October 25, a week ahead of the November 18 freeze normal.
Estimated water temperature by month
This is Arlington'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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 39° | 38° | 44° | 53° | 63° | 72° | 80° | 81° | 76° | 66° | 55° | 45° |
Warmest water typically July–August (peaking near 81°F); heaters and covers shift any month up.
Email me when Arlington hits the closing window
Data: NOAA 1991–2020 climate normals via Washington Reagan Airport (4.2 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.