The short answer: chinook peak the last week of September into early October, coho run through October, and steelhead run from October right through the following spring. The longer answer is that the calendar only sets the window. Water temperature and rain decide the day.
| Run | Window | Notes |
|---|---|---|
| Chinook (King) | Mid-September to mid-October | Peak is usually the last week of September into the first two weeks of October. Fish stage at river mouths in late August and push up on cooling water and fall rain. |
| Coho | Late September to November | The Platte and Betsie lead. Peak is often early to mid October. Coho tolerate a wider window than kings. |
| Fall steelhead | October to November | Steelhead follow the salmon in, feeding on eggs. They keep entering as the water cools. |
| Winter steelhead | December to February | Fish hold in deeper runs. Fishable on tailwater rivers like the Muskegon that resist freeze-up. |
| Spring steelhead | March to April | The heaviest, most active steelhead run of the year, and for many rivers the best fishing of all. |
Great Lakes salmon are in the big water all summer. Three signals bring them up the rivers in fall. Day length starts the process in late summer, priming mature fish to return. Water temperature is the trigger: chinook get moving as river temperatures slide out of the 60s into the 50s, and a river still reading 68 degrees in early September will hold fish at the mouth until it cools. Flow is the pull. A fall rain that raises and colors the river sends a fresh wave of fish upstream, which is why the fishing so reliably turns on a day or two after a good storm.
Put those together and a pattern emerges. Early September is staging: fish are stacked near the mouths, waiting. The last week of September into early October is usually the main event, especially if a cool rain lines up with it. By late October the king run is winding down and steelhead are taking over. That is the rhythm the live board is built to track.
The famous Lake Michigan rivers run on roughly the same schedule, with the peak in late September and early October. The Big Manistee below Tippy Dam gathers the largest concentrations of staging chinook in the state. The Pere Marquette, with its wild fish and flies-only water, tracks temperature and rain closely. The Muskegon below Croton Dam is big water that spreads fish out and fishes well by boat. The Little Manistee is small, wild, and the source of the region's steelhead eggs. The Platte, birthplace of the state's salmon program, is a coho river first.
On the Lake Huron side, the Au Sable below Foote Dam runs on a similar calendar, but plan it around steelhead and Atlantic salmon rather than the big king numbers of the west side, for reasons explained on that river's page.
For chinook, aim for the window from about September 20 to October 10 and stay flexible within it. Watch the forecast for a cool rain and go on the front or back of that system. For steelhead, October and November are dependable for fall fish, and late March into April is the spring peak. Whatever you target, check the live board a few days ahead so you are not driving to a river that is running warm and empty.