Pool season · Missouri
Lee's Summit Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
Lee's Summit'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.
Lee's Summit, MO — 105 swim days a yearEach dot on the bar is one week of Lee's Summit's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (April 13–May 4), solid teal is swim season, and hollow amber is the closing window ending October 16. The black marker is today — its position against the colors is the entire executive summary.
The Lee's Summit pool calendar
Opening — target April 20
Open by April 20 — a two-week head start on the May 4 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline October 16
The window opens October 6 once water leaves the algae zone; the model deadline is October 16, a week ahead of the October 29 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on Lee's Summit'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 32° | 32° | 41° | 51° | 61° | 71° | 78° | 79° | 74° | 63° | 51° | 39° |
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 Kansas City's pool season and O'Fallon's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Missouri season index.
Lee's Summit pool season FAQ
When should I open my pool in Lee's Summit, MO?
The site model recommends opening by April 20 — about two weeks before Lee's Summit'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 Lee's Summit opening guide.
When should I close my pool in Lee's Summit?
Winterize by October 16. The model holds the deadline a week ahead of Lee's Summit's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Lee's Summit closing guide.
How long is the swim season in Lee's Summit?
Lee's Summit averages 105 days a year with normal highs of 80°F or better — right on the statewide median. The Missouri season index ranks all 8 covered cities by the same metric.
How warm does pool water get in Lee's Summit?
An unheated pool near Lee's Summit typically peaks around 79°F in high summer and bottoms out near 31°F in winter, spending roughly 1 month 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 Lee's Summit hits the closing window
Data: NOAA 1991–2020 climate normals via Lees Summit Municipal Airport (3.0 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.