PoolWindow

Pool season · California

Redlands Pool Season: the Year on One Bar

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

Redlands'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 climateRedlands, CA — 166 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 Redlands's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (March 22–April 12), solid teal is swim season, and hollow amber is the closing window ending November 23. The black marker is today — its position against the colors is the entire executive summary.

The Redlands pool calendar

March 29open by
November 23close by
16680°F+ days
80°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 23

The window opens November 13 once water leaves the algae zone; the model deadline is November 23, a week ahead of the December 19 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 Redlands water runs about 53°F at its winter floor and 80°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 Redlands'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 2380°F peak53°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Redlands — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
53°54°56°60°64°69°77°80°78°72°64°56°

Warmest water typically August–September (peaking near 80°F); heaters and covers shift any month up.

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

Redlands pool season FAQ

When should I open my pool in Redlands, CA?

The site model recommends opening by March 29 — about two weeks before Redlands's 7-day mean temperature crosses 61°F, while the water is still too cold for algae. The step-by-step sequence is in the Redlands opening guide.

When should I close my pool in Redlands?

Winterize by November 23. The model holds the deadline a week ahead of Redlands's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Redlands closing guide.

How long is the swim season in Redlands?

Redlands averages 166 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 Redlands?

An unheated pool near Redlands typically peaks around 80°F in high summer and bottoms out near 53°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 Redlands (1.7 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.