Wind direction and waves at each Lake St. Clair area
Waves grow with the wind speed, the distance of open water upwind (the fetch) and the water depth. For each of the 12 smallmouth areas of Lake St. Clair and the 8 compass directions, this page shows where the CastScience Wave Prediction, the significant wave height (Hs, the average of the highest third of the waves), stays at 1.0 ft or less in a 15 mph wind over the water, and where the water is roughest. The largest wave in about an hour is about 1.86 times Hs.
By wind direction
Up to 1.0 ft the app counts the water as fishable with every bottom presentation; above 2.0 ft it shows a wave caution. Heights to 0.1 ft, as on the area pages.
At 20 mph, Hs is above 2.0 ft at 7 of the 96 area and direction pairs: Belle River Hump area from N, 2.3 ft; Middle Channel outflow from S, 2.2 ft; U.S. main basin east of the Mile Roads from SE, 2.2 ft; U.S. main basin east of the Mile Roads from E, 2.1 ft; Belle River Hump area from E, 2.1 ft; South shore toward the Detroit River (Tecumseh to Puce) from E, 2.1 ft; Belle River Hump area from NE, 2.1 ft.
By area
| Area | Depth (wave depth) | Sheltered at 15 mph from | Roughest direction: fetch, Hs at 15 and 20 mph |
|---|---|---|---|
| Middle Channel outflow, outer Anchor Bay edge | 12-18 ft (4.5 m) | NE, E, SE | S: 28.8 km (17.9 mi), 1.6 ft and 2.2 ft |
| North Channel outflow, north-east Anchor Bay | 12-18 ft (4.5 m) | every direction | NW: 7.2 km (4.4 mi), 1.0 ft and 1.4 ft |
| Metropark to Selfridge flats, Clinton River mouth | 6-12 ft (2.7 m) | N, E, SE, SW, W, NW | S: 33.6 km (20.9 mi), 1.4 ft and 1.8 ft |
| Mile Roads, St. Clair Shores (9 to 13 Mile) | 8-14 ft (3.4 m) | N, SW, W, NW | SE: 30.8 km (19.1 mi), 1.5 ft and 2.0 ft |
| Gaukler Point boulder ledge, Grosse Pointe Shores | 6-12 ft (2.7 m) | N, SW, W, NW | E: 36.8 km (22.9 mi), 1.4 ft and 1.8 ft |
| Gaukler Point boulder ledge, off the point | 3-6 ft (2.0 m) | N, S, SW, W, NW | E: 37.4 km (23.2 mi), 1.2 ft and 1.5 ft |
| U.S. main basin east of the Mile Roads | 14-19 ft (4.5 m) | none | SE: 27.9 km (17.3 mi), 1.6 ft and 2.2 ft |
| Belle River Hump area | 15-19 ft (4.5 m) | S, SW | N: 36.5 km (22.7 mi), 1.7 ft and 2.3 ft |
| South shore toward the Detroit River (Tecumseh to Puce) | 10-14 ft (3.7 m) | S, SW, W, NW | E: 33.2 km (20.6 mi), 1.6 ft and 2.1 ft |
| South shore east: Stoney Point to Thames River mouth | 4-10 ft (2.1 m) | NE, E, SE, S, SW | NW: 36.2 km (22.5 mi), 1.2 ft and 1.5 ft |
| Canadian main basin, east of the channel | 16-21 ft (4.5 m) | none | NW: 22.8 km (14.1 mi), 1.5 ft and 2.0 ft |
| East shore flats off Mitchell's Bay | 6-12 ft (2.7 m) | N, NE, E, SE, NW | W: 34.2 km (21.3 mi), 1.4 ft and 1.8 ft |
Fetch: open water upwind of the area, measured on the lake outline in 36 directions. Wave depth: the middle of the area's depth range, kept between 2 and 4.5 m. Each area's page has its whole table: the fetch, Hs and the largest wave for every direction at 10, 15, 20 and 25 mph.
Accuracy
Wave heights are model estimates from forecast wind, not measurements. Checked against the mid-lake buoy (2003-2026), the highest waves of a 12-hour period were 25% or more above the estimate in 1 period in 5, and in 2 periods in 5 when waves were above 2 ft. Check the marine forecast and the water at the launch before you go. The decision to go out is yours. Full text
The speeds are the wind over the water, which differs from the wind at a shore station (Wind over water). The plan applies the same model, fetch and depths to the forecast wind of each hour.
Sources and related pages
- Method: the U.S. Army Corps of Engineers Shore Protection Manual (1984) shallow-water wave method, as the area pages and the plan use it.
- Lake outline: U.S. Geological Survey National Hydrography Dataset. Areas, depth ranges and evidence: the app's area records.
- Waves: fetch, depth, Hs and the largest wave, and the two wave models compared
- Wave calculator: wave height from any wind, fetch and depth
- Lake St. Clair areas: each area with its whole wave table
- Plan: the forecast wind for each hour applied to these tables, with your boat's wave limit