PoolWindow

Pool season · California

Yuba City Pool Season: the Year on One Bar

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

Yuba City's whole pool calendar, condensed: when the water warms, when it cools, and where today falls between those edges. Use the opening guide and closing guide for the step-by-step work; keep this page for the dates.

Resort pool at dusk in a hot, long-season climateYuba City, CA — 163 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

Reading it takes ten seconds: 52 dots, one per week. Solid teal is Yuba City's swim season; the hollow teal run before it (March 22 to April 12) is when to open; the hollow amber run after is when to close, with November 9 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Yuba City pool calendar

March 29open by
November 9close by
16380°F+ days
81°Fwater peak

Opening — target March 29

Target March 29; the practical window runs March 22–April 12, and the 7-day mean crosses the 61°F threshold around April 12. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline November 9

The window opens October 30 once water leaves the algae zone; the model deadline is November 9, a week ahead of the December 12 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 Yuba City water runs about 48°F at its winter floor and 81°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 Yuba City's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.

40°50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen Mar 29close Nov 981°F peak48°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Marysville — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
48°51°55°59°66°73°79°81°78°71°60°51°

Warmest water typically July–September (peaking near 81°F); heaters and covers shift any month up.

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

Yuba City pool season FAQ

When should I open my pool in Yuba City, CA?

Target March 29. That date backs off two weeks from the day Yuba City's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Yuba City opening guide.

When should I close my pool in Yuba City?

The closing deadline is November 9 — late enough that the water has cooled out of the algae zone, early enough to beat Yuba City's first-freeze normal by about a week. See the Yuba City closing guide for the winterizing steps.

How long is the swim season in Yuba City?

Yuba City averages 163 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 Yuba City?

An unheated pool near Yuba City typically peaks around 81°F in high summer and bottoms out near 48°F in winter, spending roughly 2 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 Marysville (2.9 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.