Pool season · Tennessee
Knoxville Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
One bar, one year, one Knoxville 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.
Knoxville, TN — 126 swim days a yearReading it takes ten seconds: 52 dots, one per week. Solid teal is Knoxville's swim season; the hollow teal run before it (April 7 to April 28) is when to open; the hollow amber run after is when to close, with October 21 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Knoxville pool calendar
Opening — target April 14
Target April 14; the practical window runs April 7–April 28, and the 7-day mean crosses the 61°F threshold around April 28. Cold-water starts are the cheap ones.
Closing — deadline October 21
Hold the cover until October 11, then winterize by October 21, a week ahead of the October 28 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
Monthly averages of the site's water model run on Knoxville'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 38° | 38° | 45° | 53° | 62° | 71° | 76° | 77° | 74° | 65° | 53° | 44° |
The curve peaks near 77°F — comfortable-water months here usually involve a heater or a solar cover.
Every station tells its own story: compare this curve with Kingsport's pool season and Memphis's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Tennessee season index.
Knoxville pool season FAQ
When should I open my pool in Knoxville, TN?
The site model recommends opening by April 14 — about two weeks before Knoxville'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 Knoxville opening guide.
When should I close my pool in Knoxville?
Winterize by October 21. The model holds the deadline a week ahead of Knoxville's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Knoxville closing guide.
How long is the swim season in Knoxville?
Knoxville averages 126 days a year with normal highs of 80°F or better — about 5 days later than the Tennessee median. The Tennessee season index ranks all 14 covered cities by the same metric.
How warm does pool water get in Knoxville?
An unheated pool near Knoxville typically peaks around 77°F in high summer and bottoms out near 37°F in winter, never quite reaching the 78°F comfort line without a heater or solar cover. The month-by-month curve above shows the whole cycle; the methodology page explains the ±5°F error bars.
Email me when Knoxville hits the closing window
Data: NOAA 1991–2020 climate normals via Knoxville Experiment Station (4.9 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.