Pool season · Colorado
Aurora Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
Aurora'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.
Aurora, CO — 105 swim days a yearThe bar compresses Aurora's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the May 8–May 29 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 1. Wherever the today marker sits, the nearest color change is your next appointment.
The Aurora pool calendar
Opening — target May 15
Open by May 15 — a two-week head start on the May 29 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline October 1
The window opens September 22 once water leaves the algae zone; the model deadline is October 1, a week ahead of the October 8 freeze normal.
Estimated water temperature by month
Monthly averages of the site's water model run on Aurora's own normals — the shape of a typical year, not a forecast. The widget above shows where the current year actually sits.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 32° | 33° | 38° | 45° | 52° | 63° | 72° | 73° | 68° | 57° | 45° | 35° |
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 Arvada's pool season and Boulder's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Colorado season index.
Aurora pool season FAQ
When should I open my pool in Aurora, CO?
The site model recommends opening by May 15 — about two weeks before Aurora'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 Aurora opening guide.
When should I close my pool in Aurora?
Winterize by October 1. The model holds the deadline a week ahead of Aurora's NOAA 50% first-freeze date, so the plumbing is protected before the first hard night. The full sequence is in the Aurora closing guide.
How long is the swim season in Aurora?
Aurora averages 105 days a year with normal highs of 80°F or better — right on the statewide median. The Colorado season index ranks all 19 covered cities by the same metric.
How warm does pool water get in Aurora?
An unheated pool near Aurora typically peaks around 74°F in high summer and bottoms out near 32°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 Aurora hits the closing window
Data: NOAA 1991–2020 climate normals via Cherry Creek Dam (8.1 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.