Pool season · Mississippi
Hattiesburg Pool Season: the Year on One Bar
Last updated: July 15, 2026 · dates · water temp
Hattiesburg'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.
Each dot on the bar is one week of Hattiesburg's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (March 2–March 23), solid teal is swim season, and hollow amber is the closing window ending November 13. The black marker is today — its position against the colors is the entire executive summary.
The Hattiesburg pool calendar
Opening — target March 9
Target March 9; the practical window runs March 2–March 23, and the 7-day mean crosses the 61°F threshold around March 23. Cold-water starts are the cheap ones.
Closing — deadline November 13
Hold the cover until November 3, then winterize by November 13, a week ahead of the November 23 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
This is Hattiesburg'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 49° | 50° | 56° | 63° | 70° | 77° | 81° | 82° | 80° | 73° | 62° | 54° |
Warmest water typically July–September (peaking near 82°F); heaters and covers shift any month up.
Email me when Hattiesburg hits the closing window
Data: NOAA 1991–2020 climate normals via Hattiesburg 5sw (3.9 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.