Lake levels
How fast is the lake actually moving?
"The lake is dropping" is true every summer. The useful questions are how fast, compared with what, and from where it started — and for this year those three answers do not point the same way. Here is Okanagan Lake week by week against the modern drought year (2003), the modern flood year (2017) and the 1944–2025 normal.
Where the lake sits
How fast it is moving
The same record, differenced: how many millimetres the lake gained or lost each week. This is the panel that answers "is this year unusual right now", which the level trace above cannot — two years can sit at the same elevation in July and be heading in quite different directions.
Decline from each year's own peak
A third view, and the fairest comparison between years: how far each year has fallen from its own high point. Measuring from full pool instead would charge a year for water it never received.