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Pool season · Minnesota

Minneapolis Pool Season: the Year on One Bar

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

Minneapolis'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.

Cool blue pool in a short-season northern climateMinneapolis, MN — 58 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

The bar compresses Minneapolis's whole pool year into one lane rope: gray floats for the off-season, hollow teal for the May 1–May 22 opening window, solid teal for swim weeks, hollow amber for the closing stretch that ends September 30. Wherever the today marker sits, the nearest color change is your next appointment.

The Minneapolis pool calendar

May 8open by
September 30close by
5880°F+ days
74°Fwater peak

Opening — target May 8

Open by May 8 — a two-week head start on the May 22 crossing keeps startup chemistry small and beats the local service rush.

Full opening guide

Closing — deadline September 30

The window opens September 20 once water leaves the algae zone; the model deadline is September 30, a week ahead of the October 16 freeze normal.

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 Minneapolis water runs about 15°F at its winter floor and 74°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 Minneapolis'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.

10°20°30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDec65° algae zone58° swimmable startopen May 8close Sep 3074°F peak15°F floor
Site-model seasonal water estimates for an unheated in-ground pool near Lower St Anthony Falls — ±5°F, see methodology.
JanFebMarAprMayJunJulAugSepOctNovDec
17°16°26°40°53°65°72°73°67°56°40°26°

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 Lakeville's pool season and Plymouth's — neighboring normals stations can shift the windows by a week or more. The full ranking lives on the Minnesota season index.

Minneapolis pool season FAQ

When should I open my pool in Minneapolis, MN?

Open by May 8 — the model places Minneapolis's 61°F crossing about two weeks later, and every warm day you wait pushes the water toward the 65°F algae zone. The Minneapolis opening guide has the 12-step sequence.

When should I close my pool in Minneapolis?

Close by September 30: cool water keeps its winter chemistry, but freeze damage is the hard stop. The Minneapolis closing guide sequences the work backward from that date.

How long is the swim season in Minneapolis?

Minneapolis averages 58 days a year with normal highs of 80°F or better — right on the statewide median. The Minnesota season index ranks all 10 covered cities by the same metric.

How warm does pool water get in Minneapolis?

An unheated pool near Minneapolis typically peaks around 74°F in high summer and bottoms out near 15°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 Lower St Anthony Falls (1.4 mi); live outlook by Open-Meteo. Attribution: sources · assumptions: methodology.