mark straussman is in downtown miami next to biscayne bay where the wind is gusting at more than 60 miles per hour. mark, good morning. >> reporter: good morning, charlie. the winds you're talking about that are gusting, much more sustained as we've been standing out here in the last half hour. you can feel it. first of all stinging rain in my face. it's very difficult to standstill in spots. you may see me go flying around. you can see it in the amount of debris every where. i can see three traffic signs one there, one there and one over there that are on their sides. they are still anchored but toppled. you also see downed power line over there which i've been keeping an eye on. it was spark and stopped sparking. another indication of sustained wind miami beach no longer responding to emergency calls. once the winds get sustained at 40 miles per hour or higher, they made a decision they were going to stop. we have reached that point. anyone who has decided to ride out the storm on miami beach decided to hunker down there. essentially they are on their own. there could be some serious ca

mark straussman is in downtown miami with a look at the damage. mark, good morning. >> reporter: good morning, norah. this severed tree limb is just one of the reasons why to drive through downtown miami you have to weave your way around wreckage of trees and power lines because high winds, hurricane force winds, and up to 5 1/2 feet of storm surge swept through this downtown area. in fact, so much storm surge and the winds were so high that parts of the skyline, the tall buildings in downtown miami, looked like they had been planted on islands. power outages were a huge problem as well. florida power and light, the main utility here, says at one point 85% of its customer base, homes and businesses, were in the dark. that's more than 2 million customers. restoring that power is going to take weeks. the hurricane force winds also sheared rooftops and gouged at buildings, the facades of them. some of the buildings included construction projects. two cranes, a couple miles apart, both snapped. a third one snapped in ft. lauderdale. no reports of inju

mark straussman is on the coast here in miami beach. mark, good morning. >> reporter: good morning. more than 700,000 people here in miami-dade county under a mandatory evacuation order. you can tell most have taken it seriously. take a look. this is south beach, a couple blocks from the atlantic ocean boarded up, closed for business. people studied the radar and hit the road. irma's storm surge could put this neighborhood in high water and deep trouble. gridlock gripped roads from miami to orlando as tens of thousands scramble to evacuate. on miami beach, families piled up sandbags trying to protect their homes from the storm. >> i'm scared. >> reporter: sheri schwartz live as half mile from the beach and told us her neighbors are staying put, but she's not. >> i would like to be in denial, but this time i'm taking heed and getting out. >> reporter: on average, miami beach sits about four feet above sea level. storm surges from irma here could reach three to six feet. governor rick scott issued evacuation orders across the state. >> i stay. >> reporter: but there are still holdouts

mark straussman is in downtown, miami. i know officials were very concerned about those cranes. some of them as high as 900 feet tall. >> good morning, concerned about a lot of things, including those cranes. and this street which you wouldn't recognize. brickell avenue, major downtown miami street, unrecognizable. some of the most major damage here is right in the heart of downtown miami. this symbol of miami's economic growth became one of the city's most high-profile storm victims sunday morning. a construction claim on top of a new 30-story building snapped under winds nearing 100 miles per hour. a little over an hour later, a second crane collapsed. a few miles north in the edgewater neighborhood where lincoln lives. >> these cranes that are 45, 50 stories up if they fall, they have the potential to go three or four blocks and everyone in that area should have been evacuated. >> a third crane up the coast in ft. lauderdale crumpled in i irma's winds. they won't start a full assessment of the damage until later today. elsewhere in miami, gusts ripped the roof off this buildi