Mich. Comp. Laws § 31.4: Governor; successor, exercise of powers and discharge of duties.

Sec. 4.

If the governor, lieutenant governor, the elected secretary of state, the elected attorney general, the president pro tempore of the senate and speaker of the house of representatives are not able or are unavailable to exercise the powers and discharge the duties of the governor because of a disaster, the available emergency interim successor highest in order of succession shall exercise the powers and discharge the duties of the office of governor until a new governor is elected and qualified, or until a preceding named officer becomes available. No emergency interim successor to the aforementioned offices, other than governor, may serve as governor.