Fla. Stat. § 14.056
Upon impeachment of the Governor and until completion of trial thereof, or during the Governor's physical or mental incapacity, the Lieutenant Governor shall become Acting Governor. Upon impeachment or physical or mental incapacity of an Acting Governor, or upon vacancy in the office of the person serving as Acting Governor, the powers and duties of Acting Governor shall devolve upon the same officer as in the case of vacancy in the office of Governor. A successor shall serve until the disability of either the Lieutenant Governor or Governor ceases. Incapacity and restoration of capacity to serve as Acting Governor shall be determined in the same manner as in making such determinations for Governor. In any case in which succession as Acting Governor is not provided herein, the Speaker of the House and the President of the Senate shall convene the Legislature by joint proclamation within 15 days for the purpose of choosing a person to serve as Acting Governor. Such person shall be elected by a majority vote in a joint session of both houses.
Fla. Stat. § 14.056