PoolWindow

Pool season · Michigan

Troy Pool Season: the Year on One Bar

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

This is the one-page view of Troy's pool year: both model windows, the estimated water-temperature curve, and today's live position on the season bar. The detailed checklists live on the opening and closing guides; this page is the calendar you check between them.

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 Troy's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the April 30–May 21 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 3. Wherever the today marker sits, the nearest color change is your next appointment.

The Troy pool calendar

May 7open by
October 3close by
6380°F+ days
73°Fwater peak

Opening — target May 7

Target May 7; the practical window runs April 30–May 21, and the 7-day mean crosses the 61°F threshold around May 21. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline October 3

Hold the cover until September 23, then winterize by October 3, a week ahead of the October 22 freeze normal. Late and cold beats early and warm.

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 Troy water runs about 24°F at its winter floor and 73°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 Troy'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 Pontiac Wwtp — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
27°24°31°42°54°65°71°72°68°58°45°35°

The curve peaks near 73°F — comfortable-water months here usually involve a heater or a solar cover.

Data: NOAA 1991–2020 climate normals via Pontiac Wwtp (6.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.