Hurricane Erin has been downgraded to a Category 3 hurricane but is gaining in size and raising the risk of life-threatening surf later this week along the U.S.

Meteorologists are closely tracking the projected path and forecast of Hurricane Erin, which is the first hurricane to develop over the Atlantic this year.

Two more tropical systems trail Hurricane Erin, which is following a projected course that brushes past the East Coast without making landfall.

Tropical storm alerts are in effect for parts of the Mid-Atlantic Coast...including a warning for parts of the North Carolina Coast. Tropical storm force winds (yellow) are expected to impact the Outer Banks by Thursday.

Much of North Carolina’s Outer Banks region is under a tropical storm watch with Hurricane Erin expected to skirt the area Wednesday through Thursday, according to the National Hurricane Center.

Tropical Storm Erin's path puts some homeowners at heightened risk, as the storm starts building into a hurricane tracked by meteorologists.

Although the storm is expected to stay offshore, it will produce dangerous surf conditions for much of the Atlantic Coast this week, forecasters say.

At 5 p.m., Erin was packing maximum sustained wind of 105 mph. The Category 2 hurricane remains on a path to steer