(a) The powers in this section may be exercised only during the effective period of an official proclamation by the Governor that declares all or part of the county to be in an actual or threatened emergency area.

(b) If a majority of the members of the local governing body of a county are killed or are sick, incapacitated, missing, or otherwise unavailable for a temporary or indefinite period because of a military or warlike catastrophe, the Governor may exercise the administrative and executive powers of that local governing body until the number of members of the local governing body sufficient to operate the county government are appointed and qualify.