PoolWindow

Pool season · California

Bellflower Pool Season: the Year on One Bar

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

This is the one-page view of Bellflower'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 climateBellflower, CA — 89 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 Bellflower's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the March 9–March 30 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 29. Wherever the today marker sits, the nearest color change is your next appointment.

The Bellflower pool calendar

March 16open by
November 29close by
8980°F+ days
74°Fwater peak

Opening — target March 16

Target March 16; the practical window runs March 9–March 30, and the 7-day mean crosses the 61°F threshold around March 30. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline November 29

The window opens November 19 once water leaves the algae zone; the model deadline is November 29, a week ahead of the January 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 Bellflower water runs about 56°F at its winter floor and 74°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 Bellflower'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.

50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Mar 16close Nov 2974°F peak56°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Long Beach Daugherty Field — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
57°57°59°61°64°67°71°74°74°71°65°58°

The curve peaks near 74°F — comfortable-water months here usually involve a heater or a solar cover.

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

Bellflower pool season FAQ

When should I open my pool in Bellflower, CA?

Open by March 16 — the model places Bellflower's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Bellflower opening guide has the 12-step sequence.

When should I close my pool in Bellflower?

Close by November 29: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Bellflower closing guide sequences the work backward from that date.

How long is the swim season in Bellflower?

Bellflower averages 89 days a year with normal highs of 80°F or better — about 16 days earlier than the California median. The California season index ranks all 147 covered cities by the same metric.

How warm does pool water get in Bellflower?

An unheated pool near Bellflower typically peaks around 74°F in high summer and bottoms out near 56°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 Long Beach Daugherty Field (5.4 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.