Roger,
Members of this forum usually recommend the Davis line of weather stations as best value. The rather harsh conditions (salty air) would add more weight to that recommendation. Your statement "I need a system that can be hard wired with battery back up as we have frequent power outages." is a little hard to interpret. Are you saying you need a cabled model or are you saying you need a battery backed up system? You could say that the Davis is a solar powered system with a battery back-up (both cabled and wireless) which can run off household electricity when its available. You probably should go to the Davis web site and do a little study then ask more questions.
FWIW as a start.
George