Pool season · Colorado
Lafayette Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
Lafayette'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.
Lafayette, CO — 109 swim days a yearThe bar compresses Lafayette's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the May 2–May 23 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends October 4. Wherever the today marker sits, the nearest color change is your next appointment.
The Lafayette pool calendar
Opening — target May 9
Open by May 9 — a two-week head start on the May 23 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline October 4
Hold the cover until September 25, then winterize by October 4, a week ahead of the October 11 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
This is Lafayette'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 33° | 34° | 39° | 47° | 54° | 65° | 73° | 75° | 70° | 58° | 46° | 36° |
The curve peaks near 75°F — comfortable-water months here usually involve a heater or a solar cover.
Every station tells its own story: compare this curve with Highlands Ranch's pool season and Lakewood's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Colorado season index.
Lafayette pool season FAQ
When should I open my pool in Lafayette, CO?
Open by May 9 — the model places Lafayette's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Lafayette opening guide has the 12-step sequence.
When should I close my pool in Lafayette?
Close by October 4: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Lafayette closing guide sequences the work backward from that date.
How long is the swim season in Lafayette?
Lafayette averages 109 days a year with normal highs of 80°F or better — about 4 days earlier than the Colorado median. The Colorado season index ranks all 19 covered cities by the same metric.
How warm does pool water get in Lafayette?
An unheated pool near Lafayette typically peaks around 75°F in high summer and bottoms out near 33°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 Lafayette hits the closing window
Data: NOAA 1991–2020 climate normals via Northglenn (8.0 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.