Transcript for East Coast Bracing For Monster Tropical Storm Arthur
Millions of Americans are watching this tonight, the Mon steb tropical storm churning off the coast line. Hurricane warnings going up just as we come on the air tonight. Look at the view from space this evening. Arthur is 450 miles wide. Winds are already gusting up to 80 miles per hour or more and it's just the beginning. With the 4th of July families are bracing for Arthur, already a state of emergency on the coast line, expecting to get hit hard. We have team coverage up and down the coast. But first we want to get right to it. Meteorologist ginger zee is tracking this hour by hour. Where is it now? Still about 400 miles from the North Carolina coast that will be affected most. At this hour what we are most concerned about, David, would be those hurricane warnings. Even a mandatory evacuation just put into place for hat Russ island. So you're seeing all the cities there and the red is what we're really concerned about, 80 plus miles per hour gusts, did you feel rough surf and coast Al floods for tomorrow night and early tomorrow morning. This will become our first hurricane for the atlantic season. You're watching it skirt by on the Carolina coast and it goes off to the sea. Much of the east coast is going to miss out. A big reason? The water temperature. You see the 80s and 90s. You need the 90s to full a hurricane. As it goes to the 70s and 60s it's going to kill it. We'll put it together in a future cast. This is how it's going to play out. It gets onshore midnight Friday. Then the cold front squeezes together. Parts of Washington D.C. Will be rainy Friday morning but drying out Friday night. A problem for Friday night is Connecticut to Boston. We learned Boston has moved its fireworks up by a day. Absolutely, from the mid-atlantic through new England and the southeast. One of the real dangers as you pointed out, the rough seas
This transcript has been automatically generated and may not be 100% accurate.