PoolWindow

Pool season · New York

Bronx Pool Season: the Year on One Bar

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

This is the one-page view of Bronx'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.

Cool blue pool in a short-season northern climateBronx, NY — 87 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

Each dot on the bar is one week of Bronx'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 17–May 8), solid teal is swim season, and hollow amber is the closing window ending October 18. The black marker is today — its position against the colors is the entire executive summary.

The Bronx pool calendar

April 24open by
October 18close by
8780°F+ days
78°Fwater peak

Opening — target April 24

Open by April 24 — a two-week head start on the May 8 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline October 18

Hold the cover until October 8, then winterize by October 18, a week ahead of the November 16 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 Bronx water runs about 33°F at its winter floor and 78°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 Bronx'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 24close Oct 1878°F peak33°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Bronx — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
35°34°39°48°59°69°77°78°74°64°52°43°

Warmest water typically August–August (peaking near 78°F); heaters and covers shift any month up.

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

Bronx pool season FAQ

When should I open my pool in Bronx, NY?

Open by April 24 — the model places Bronx's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Bronx opening guide has the 12-step sequence.

When should I close my pool in Bronx?

Close by October 18: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Bronx closing guide sequences the work backward from that date.

How long is the swim season in Bronx?

Bronx averages 87 days a year with normal highs of 80°F or better — about 12 days earlier than the New York median. The New York season index ranks all 16 covered cities by the same metric.

How warm does pool water get in Bronx?

An unheated pool near Bronx typically peaks around 78°F in high summer and bottoms out near 33°F in winter, never quite reaching the 78°F comfort line without a heater or solar cover. 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 Bronx (1.2 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.