PoolWindow

Pool season · Connecticut

Norwich Pool Season: the Year on One Bar

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

One bar, one year, one Norwich 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.

Cool blue pool in a short-season northern climateNorwich, CT — 73 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

Reading it takes ten seconds: 52 dots, one per week. Solid teal is Norwich's swim season; the hollow teal run before it (May 1 to May 22) is when to open; the hollow amber run after is when to close, with October 7 as the deadline; gray is the covered season. Today's marker shows where you stand in that cycle right now.

The Norwich pool calendar

May 8open by
October 7close by
7380°F+ days
75°Fwater peak

Opening — target May 8

Target May 8; the practical window runs May 1–May 22, and the 7-day mean crosses the 61°F threshold around May 22. Cold-water starts are the cheap ones.

Full opening guide

Closing — deadline October 7

Hold the cover until September 27, then winterize by October 7, a week ahead of the October 24 freeze normal. Late and cold beats early and warm.

Full closing guide

Where the water sits today

SEASONAL VIEW

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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 Norwich water runs about 29°F at its winter floor and 75°F at its summer peak.

40 45 50 55 60 65 70 75 80 85 58 open 65 algae

Estimated water temperature by month

This is Norwich'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.

20°30°40°50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen May 8close Oct 775°F peak29°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Norwich Public Utility Plt — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
32°30°35°44°55°64°73°74°69°59°48°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 Norwalk's pool season and Stamford's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Connecticut season index.

Norwich pool season FAQ

When should I open my pool in Norwich, CT?

Target May 8. That date backs off two weeks from the day Norwich's 7-day mean temperature reaches 61°F, so you start up in cold, algae-resistant water. Work the full checklist in the Norwich opening guide.

When should I close my pool in Norwich?

The closing deadline is October 7 — late enough that the water has cooled out of the algae zone, early enough to beat Norwich's first-freeze normal by about a week. See the Norwich closing guide for the winterizing steps.

How long is the swim season in Norwich?

Norwich averages 73 days a year with normal highs of 80°F or better — right on the statewide median. The Connecticut season index ranks all 8 covered cities by the same metric.

How warm does pool water get in Norwich?

An unheated pool near Norwich typically peaks around 75°F in high summer and bottoms out near 29°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.

Data: NOAA 1991–2020 climate normals via Norwich Public Utility Plt (2.0 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.