Rising water is in the forecast along some already flooding Lower Peninsula rivers as rain falls on saturated watersheds.
The National Weather Service says the Saginaw River at Saginaw in central Michigan was 2.6 feet above flood stage Wednesday. It should crest at 5 feet above flood stage Sunday or Monday.
Up to 4 inches of rain could fall on parts of the state through Friday.
In western Michigan, the weather service says the Grand River was 2.3 feet over flood stage upstream from Grand Rapids and was 1.4 feet over farther downstream in Ottawa County's Robinson Township.
Other flooded rivers include the Rifle River north of Bay City and the Muskegon River near Muskegon.
Newaygo County has declared a state of emergency for its portion of the Muskegon River.