PoolWindow

Pool season · New Jersey

Jersey City Pool Season: the Year on One Bar

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

This is the one-page view of Jersey City'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 climateJersey City, NJ — 91 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 Jersey City'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 19–May 10), solid teal is swim season, and hollow amber is the closing window ending October 15. The black marker is today — its position against the colors is the entire executive summary.

The Jersey City pool calendar

April 26open by
October 15close by
9180°F+ days
78°Fwater peak

Opening — target April 26

Target April 26; the practical window runs April 19–May 10, and the 7-day mean crosses the 61°F threshold around May 10. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline October 15

The window opens October 5 once water leaves the algae zone; the model deadline is October 15, a week ahead of the November 6 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 Jersey City water runs about 32°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

Monthly averages of the site's water model run on Jersey City's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.

20°30°40°50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Apr 26close Oct 1578°F peak32°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Harrison — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
34°33°38°47°58°68°76°77°73°63°51°41°

The curve peaks near 78°F — comfortable-water months here usually involve a heater or a solar cover.

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

Jersey City pool season FAQ

When should I open my pool in Jersey City, NJ?

Open by April 26 — the model places Jersey City's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Jersey City opening guide has the 12-step sequence.

When should I close my pool in Jersey City?

Close by October 15: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Jersey City closing guide sequences the work backward from that date.

How long is the swim season in Jersey City?

Jersey City averages 91 days a year with normal highs of 80°F or better — about 4 days earlier than the New Jersey median. The New Jersey season index ranks all 7 covered cities by the same metric.

How warm does pool water get in Jersey City?

An unheated pool near Jersey City typically peaks around 78°F in high summer and bottoms out near 32°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 Harrison (4.8 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.