PoolWindow

Pool season · Missouri

Kansas City Pool Season: the Year on One Bar

Last updated: July 25, 2026 · dates · water temp

One bar, one year, one Kansas City 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.

Courtyard swimming pool at dawn in a temperate climateKansas City, MO — 114 swim days a year
J F M A M J J A S O N D today (build date)

off-season opening window swim season closing window

The bar compresses Kansas City's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 9–April 30 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 20. Wherever the today marker sits, the nearest color change is your next appointment.

The Kansas City pool calendar

April 16open by
October 20close by
11480°F+ days
81°Fwater peak

Opening — target April 16

Open by April 16 — a two-week head start on the April 30 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline October 20

The window opens October 10 once water leaves the algae zone; the model deadline is October 20, a week ahead of the November 2 freeze normal.

Full closing guide

Where the water sits today

SEASONAL VIEW

Estimated unheated pool water temp (site model, ±5°F). The live estimate loads in your browser from Open-Meteo air temperatures; in a typical year Kansas City water runs about 31°F at its winter floor and 81°F at its summer peak.

40 45 50 55 60 65 70 75 80 85 58 open 65 algae

Estimated water temperature by month

This is Kansas City'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.

20°30°40°50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Apr 16close Oct 2081°F peak31°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Kansas City Downtown Airport — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
32°33°42°52°62°73°80°81°75°65°51°40°

Warmest water typically July–August (peaking near 81°F); heaters and covers shift any month up.

Every station tells its own story: compare this curve with Joplin's pool season and Lee's Summit's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Missouri season index.

Kansas City pool season FAQ

When should I open my pool in Kansas City, MO?

Target April 16. That date backs off two weeks from the day Kansas City's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Kansas City opening guide.

When should I close my pool in Kansas City?

The closing deadline is October 20 — late enough that the water has cooled out of the algae zone, early enough to beat Kansas City's first-freeze normal by about a week. See the Kansas City closing guide for the winterizing steps.

How long is the swim season in Kansas City?

Kansas City averages 114 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 Kansas City?

An unheated pool near Kansas City typically peaks around 81°F in high summer and bottoms out near 31°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.

Data: NOAA 1991–2020 climate normals via Kansas City Downtown Airport (2.3 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.