How it works

This is a forecast of surface texture along the usual west-shore lane, not a reading from the lake and not a launch decision.

Schematic only. The exact 5 km turnaround is not yet recorded.

Farther from center = more wave-building exposure for the route.

Inputs and assumptions

Open-Meteo supplies hourly 10 m wind, gust, and direction at the boathouse. The model weights winds by approximate over-water fetch: south and southeast are most exposed; west and southwest are sheltered by the nearby shore. It also considers the prior three hours because waves do not vanish when the wind drops at 5:00.

What the words mean

GlassFlatLight chopChoppy

Glass is strict: essentially mirror-like, with forecast wind ≤3 mph, gusts ≤5 mph, and calm recent history.
Flat allows small ripples. Light chop begins to affect blade work; choppy means that effect is likely material.

“Rowable” is intentionally not a rating. Shell, crew, coaching launch, wakes, visibility, debris, lightning, and water temperature all matter. Observe the lake and follow coach judgment.

Basis

The route assumption comes from the SRA traffic pattern and local input. Lake shape is checked against King County and USGS mapping. Fetch treatment follows inland wind-wave guidance; terminology follows ordinary rowing usage.