What have you found when looking? Worth looking at other Florida airports. Not just MIA
Feb (winter) is a popular time to visit Florida. Even USA west coast to Florida can be pricey
http://www.gcmap.com/mapui?P=c%3Ablue%2C+BNE-DFW-MIA%2C+BNE-SFO-MIA%2C+LAX%2C+ORD%2C+NYC%2C+HNL&MS=bm&PW=3&DU=mi