BrrChecker

Alster water temperature

Alster · Lake

The current water temperature at Alster is 18.3 °C (as of September 5, 2026, source: Badegewässer Hamburg (BUE/BUKEA)).

Lakes stratify in summer: bathing-warm on top, markedly colder a few metres down. Measurements are taken at the surface — right where you swim.

18.3 °C
Measured: September 5, 2026 · continuously updated
💧 Water 18.3° · ☀️ Air 13.5° · high today 16.9°
Temperature trend of recent weeks
Alster
Photo: Andreas Geick · CC BY-SA 3.0 · Wikimedia Commons

Measurement series & statistics

This measurement series includes 129 data points since July 21, 2026.

Lowest recorded value: 18.2 °C on September 5, 2026 · highest value: 24.0 °C on August 6, 2026.

In September, temperatures have ranged between 18.2 °C and 19.5 °C.

The current value is 0.6 °C below the September average of this series.

Nearby waters

Frequently asked questions

Can you swim at Alster right now?
The current water temperature is 18.3 °C. See live swimming conditions, weather and quality in the BrrChecker app.

How warm is the water at Alster?
Currently 18.3 °C (updated continuously).

How warm is at Alster in September?
In September, the water temperature recently averaged 18.9 °C.

When is the water warmest at Alster?
Across the measurement record, August is on average the warmest month (21.3 °C).

Open in the BrrChecker app

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