Mich. Comp. Laws § 31.10

Sec. 10. In the event of a disaster in this state, the governor or the secretary of state, or any deputy or emergency interim successor exercising the powers and discharging the duties of the offices, shall determine if any officer or his deputy is not able or is unavailable to exercise the powers and discharge the duties of an office, and if any officer or deputy is determined to be unavailable, the governor or the secretary of state, or any deputy or emergency interim successor exercising the powers and discharging the duties of the offices, shall inform the next available emergency interim successor so that he may exercise the powers and discharge the duties of the office.