The process whose specific outcome is the progression of the metanephric thick ascending limb over time, from its formation to the mature structure. The metanephric thick ascending limb is the last part of the metanephric loop of Henle. Its thick, mitochondria-rich epithelium characterizes the outer medulla, and is responsible for very avid active salt transport. At the macula densa, the thick ascending limb connects to the distal convoluted tubule. [ GOC:mtg_kidney_jan10 ]