Berlin Winter Swim Lake Board: How Cold the Lakes Get
Nine Berlin lake and river gauges you are allowed to swim at, on one map and one chart: how fast each cooled through the last two winters, when it dropped under 10, 6 and 4 °C, and when it warmed up again.
Daily water temperatures from the Berlin Wasserportal, checked on 29 September 2026.
Berlin lakes sit around 16 to 18 °C at the end of September and fall under 4 °C by late December. This board shows each legal swimming water day by day through the last two winters, so you can see when your lake crosses the temperature you want to start at, and how the lakes compare on any single day.
What the board shows
Nine water temperature gauges on lakes and rivers where swimming is allowed in Berlin, from the Orankesee and the Plötzensee to the Müggelsee, the Havel near Wannsee and the Zeuthener See. Pick one and the chart draws its daily water temperature from October to mid April for the last two winters, with the other gauges in grey behind it. Tap or drag across the chart and the map colours every gauge for that day.
Where the numbers come from
Daily mean water temperature from the Berlin Wasserportal gauges run by the Land Berlin, downloaded on 29 September 2026. A few days with a broken sensor are left blank.
Only waters on the official bathing list are included. Several lakes, such as the Orankesee, the Weißer See and the Plötzensee, are bathing water only inside their lidos, which are closed in winter; the note under each gauge says so.
Map outlines of districts and waters from the Geoportal Berlin.
How to read the answer
The yellow box tells you when the chosen water dropped under 10, 6 and 4 °C, how many days it stayed under 4 °C, and when it climbed back above 8 °C. October and early November, at 10 to 14 °C, are the easy weeks to start. A gauge sits at one point and depth, so on a frosty morning the surface at your entry spot can be colder than the reading. Never swim alone.