At some point Arrow Air made the wise decision not to head toward the very high terrain of Bogota, and diverted to Medellin.
Medallin is roughly 7,200 feet, Bogata is at 8,300. The approach into Medellin is more difficult because of terrain. I remember getting EGT lights on T/O regularly out of medellin as a result of the temperature/altitude there. Bogata has a longer runway and allthough at a higher altitude the temperature is cooler.