Reference data analysis
What the year comparison shows for Lake Sarnen
Typical low point
469.26 m a.s.l.
October 29
Typical high point
469.67 m a.s.l.
June 19
Typical range
41 cm
Difference between daily medians
In the 1991-2020 reference period, Lake Sarnen's seasonal median is lowest on October 29 at 469.26 m a.s.l. and highest on June 19 at 469.67 m a.s.l.. The difference between these typical points is 41 cm. This describes the average seasonal cycle, not the largest individual fluctuation.
The 2026 curve currently contains 262 calendar days. On September 22 it shows 469.07 m a.s.l., which is 29 cm below that calendar day's median of 469.36 m a.s.l.. Compared with the same calendar day in 2025, the value is 28 cm lower.
Within the 1991-2020 reference period, the envelope reaches its highest value of 472.42 m a.s.l. on August 23 and its lowest value of 468.92 m a.s.l. on November 20. These are extremes of the displayed reference period, not all-time records.
The analysis uses the water-level series from Sarnersee, Sarnen. Matching calendar days are compared, and the median is the middle value of the reference years. This classification does not replace flood warnings or local safety information.