PoolWindow

Pool season · Texas

Allen Pool Season: the Year on One Bar

Last updated: July 15, 2026 · dates · water temp

Allen'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.

J F M A M J J A S O N D today (build date)

off-season opening window swim season closing window

Each dot on the bar is one week of Allen'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 13–April 3), solid teal is swim season, and hollow amber is the closing window ending November 4. The black marker is today — its position against the colors is the entire executive summary.

The Allen pool calendar

March 20open by
November 4close by
15680°F+ days
85°Fwater peak

Opening — target March 20

Open by March 20 — a two-week head start on the April 3 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline November 4

The window opens October 29 once water leaves the algae zone; the model deadline is November 4, a week ahead of the November 11 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 Allen water runs about 44°F at its winter floor and 85°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 Allen'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.

Site-model seasonal water estimates for an unheated in-ground pool near Mckinney Municipal Airport — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
45°46°53°61°68°78°83°85°81°72°60°50°

Warmest water typically June–September (peaking near 85°F); heaters and covers shift any month up.

Data: NOAA 1991–2020 climate normals via Mckinney Municipal Airport (6.9 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.