PoolWindow

Pool season · California

Hanford Pool Season: the Year on One Bar

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

This is the one-page view of Hanford'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.

Resort pool at dusk in a hot, long-season climateHanford, CA — 168 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 Hanford's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the March 22–April 12 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends November 7. Wherever the today marker sits, the nearest color change is your next appointment.

The Hanford pool calendar

March 29open by
November 7close by
16880°F+ days
82°Fwater peak

Opening — target March 29

Open by March 29 — a two-week head start on the April 12 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline November 7

Hold the cover until October 28, then winterize by November 7, a week ahead of the December 1 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 Hanford water runs about 46°F at its winter floor and 82°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 Hanford'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.

30°40°50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Mar 29close Nov 782°F peak46°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Hanford 1 S — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
46°49°55°60°66°73°80°82°78°71°60°49°

Warmest water typically July–September (peaking near 82°F); heaters and covers shift any month up.

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

Hanford pool season FAQ

When should I open my pool in Hanford, CA?

Open by March 29 — the model places Hanford's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Hanford opening guide has the 12-step sequence.

When should I close my pool in Hanford?

Close by November 7: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Hanford closing guide sequences the work backward from that date.

How long is the swim season in Hanford?

Hanford averages 168 days a year with normal highs of 80°F or better — right on the statewide median. The California season index ranks all 147 covered cities by the same metric.

How warm does pool water get in Hanford?

An unheated pool near Hanford typically peaks around 82°F in high summer and bottoms out near 46°F in winter, spending roughly 3 months at or above the 78°F comfort line most swimmers prefer. 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 Hanford 1 S (1.3 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.