; and (vii) for other programs similar in nature or purposes to the above. 119N. (a) Terminal aerodrome forecast The Administrator shall permit an air carrier operation under part 121 of title 14, Code of Federal Regulations, to operate to a destination determined to be under visual flight rules without a Terminal Aerodrome Forecast or Meteorological Aerodrome Report if a current Area Forecast, supplemented by other local weather observations or reports, is available, and an alternate airport that has an available Terminal Aerodome Forecast and weather report is specified. The air carrier shall have approved procedures for dispatch and enroute weather evaluation and shall operate under instrument flight rules enroute to the destination. (b) Limitation Without a written finding of necessity, based on objective and historical evidence of imminent threat to safety, the Administrator shall not promulgate any operation specification, policy, or guidance document that is more restrictive than, or requires procedures that are not expressly stated in, the regulations. Federal highway administration Limitation on administrative expenses (highway trust fund) (including transfer of funds) Not to exceed $439,443,925, together with advances and reimbursements received by the Federal Highway Administration, shall be obligated for necessary expenses for administration and operation of the Federal Highway Administration: Provided , That in addition, not to exceed $3,248,000 shall be transferred to the Appalachian Regional Commission in accordance with section 104(a) of title 23, United States Code. Federal-aid highways (limitation on obligations) (highway trust fund) Funds available for the implementation or execution of Federal-aid highway and highway safety construction programs authorized under titles 23 and 49, United States Code, and the provisions of the Fixing America's Surface Transportation Act shall not exceed total obligations of $44,234,212,000 for fiscal year 2018: Provided , That the Secretary may collect and spend