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

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.