WOODBURY - Nassau County Executive Ed Mangano is urging residents to evacuate low-lying areas as a nor'easter sets its sights on Long Island. Many residents across the Island are still without power, and even more are dealing with downed trees and damaged property. "Now with the impending nor'easter, we appeal to our residents once again, to their common sense, please leave those residences, find shelter out of the flood zone," Mangano said today. "It's for your own health, safety and welfare." The county will work with the Red Cross to open shelters. Officials have also begun gathering supplies and emergency vehicles, if needed.Officials urge caution ahead of approaching nor'easter