Pool season · Connecticut
Norwalk Pool Season: the Year on One Bar
Last updated: July 25, 2026 · dates · water temp
One bar, one year, one Norwalk pool. The season bar below draws everything the model knows — opening window, prime season, closing window — against today's date, with the working details one click away on the opening and closing pages.
Norwalk, CT — 79 swim days a yearReading it takes ten seconds: 52 dots, one per week. Solid teal is Norwalk's swim season; the hollow teal run before it (April 24 to May 15) is when to open; the hollow amber run after is when to close, with October 8 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.
The Norwalk pool calendar
Opening — target May 1
Open by May 1 — a two-week head start on the May 15 crossing keeps startup chemistry small and beats the local service rush.
Closing — deadline October 8
Hold the cover until September 28, then winterize by October 8, a week ahead of the October 23 freeze normal. Late and cold beats early and warm.
Estimated water temperature by month
This is Norwalk'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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 32° | 30° | 36° | 46° | 57° | 66° | 73° | 74° | 70° | 60° | 49° | 39° |
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 New Haven's pool season and Norwich's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Connecticut season index.
Norwalk pool season FAQ
When should I open my pool in Norwalk, CT?
Target May 1. That date backs off two weeks from the day Norwalk's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Norwalk opening guide.
When should I close my pool in Norwalk?
The closing deadline is October 8 — late enough that the water has cooled out of the algae zone, early enough to beat Norwalk's first-freeze normal by about a week. See the Norwalk closing guide for the winterizing steps.
How long is the swim season in Norwalk?
Norwalk averages 79 days a year with normal highs of 80°F or better — about 7 days earlier than the Connecticut median. The Connecticut season index ranks all 8 covered cities by the same metric.
How warm does pool water get in Norwalk?
An unheated pool near Norwalk typically peaks around 75°F in high summer and bottoms out near 30°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 Norwalk hits the closing window
Data: NOAA 1991–2020 climate normals via Stamford 5 N (6.6 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.