Pool season · North Carolina
Cary Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
Cary's whole pool calendar, condensed: when the water warms, when it cools, and where today falls between those edges. Use the opening guide and closing guide for the step-by-step work; keep this page for the dates.
Cary, NC — 122 swim days a yearReading it takes ten seconds: 52 dots, one per week. Solid teal is Cary's swim season; the hollow teal run before it (March 31 to April 21) is when to open; the hollow amber run after is when to close, with October 24 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Cary pool calendar
Opening — target April 7
Target April 7; the practical window runs March 31–April 21, and the 7-day mean crosses the 61°F threshold around April 21. Cold-water starts are the cheap ones.
Closing — deadline October 24
Hold the cover until October 14, then winterize by October 24, a week ahead of the November 8 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
Monthly averages of the site's water model run on Cary's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 42° | 42° | 47° | 56° | 64° | 72° | 78° | 79° | 75° | 66° | 55° | 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 Burlington's pool season and Charlotte's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the North Carolina season index.
Cary pool season FAQ
When should I open my pool in Cary, NC?
Open by April 7 — the model places Cary's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Cary opening guide has the 12-step sequence.
When should I close my pool in Cary?
Close by October 24: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Cary closing guide sequences the work backward from that date.
How long is the swim season in Cary?
Cary averages 122 days a year with normal highs of 80°F or better — right on the statewide median. The North Carolina season index ranks all 17 covered cities by the same metric.
How warm does pool water get in Cary?
An unheated pool near Cary typically peaks around 79°F in high summer and bottoms out near 41°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.
Email me when Cary hits the closing window
Data: NOAA 1991–2020 climate normals via Apex (2.9 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.