Pool season · California
El Monte Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
El Monte'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.
El Monte, CA — 130 swim days a yearEach dot on the bar is one week of El Monte's typical year, colored by what the model says that week is for: gray weeks are off-season, hollow teal marks the opening window (February 25–March 18), solid teal is swim season, and hollow amber is the closing window ending November 30. The black marker is today — its position against the colors is the entire executive summary.
The El Monte pool calendar
Opening — target March 4
Open by March 4 — a two-week head start on the March 18 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline November 30
The window opens November 20 once water leaves the algae zone; the model deadline is November 30, a week ahead of the January 2 freeze normal.
Estimated water temperature by month
This is El Monte'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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 57° | 57° | 59° | 62° | 65° | 69° | 74° | 76° | 77° | 72° | 66° | 58° |
The curve peaks near 77°F — comfortable-water months here usually involve a heater or a solar cover.
Every station tells its own story: compare this curve with El Cajon's pool season and El Paso de Robles's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the California season index.
El Monte pool season FAQ
When should I open my pool in El Monte, CA?
The site model recommends opening by March 4 — about two weeks before El Monte'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 El Monte opening guide.
When should I close my pool in El Monte?
Winterize by November 30. The model holds the deadline a week ahead of El Monte's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the El Monte closing guide.
How long is the swim season in El Monte?
El Monte averages 130 days a year with normal highs of 80°F or better — about 28 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 El Monte?
An unheated pool near El Monte typically peaks around 77°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.
Email me when El Monte hits the closing window
Data: NOAA 1991–2020 climate normals via San Gabriel Fire Dept (4.2 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.