The National Hurricane Center (NHC) is monitoring two areas to watch for tropical development behind Hurricane Erin as the Atlantic Ocean's Main Development Region roars to life.

Forecasters are tracking a new disturbance in the Atlantic Ocean as Hurricane Erin, a Category 5 storm, undergoes an eyewall replacement cycle, according to a Saturday night update from the National Hurricane Center.

Besides Erin, we are monitoring two areas of interest in the Atlantic Basin. Both are in the main development region of the Atlantic Ocean. The first has a 60% chance of tropical development over the next 7 days. The latest forecast track keeps this on a similar path as Erin initially, but a little farther to the east once it makes the turn.

Erin developed in the eastern Atlantic, moving westward from the Cabo Verde Islands at about 20 mph (32 km/h). Infrared sensors on NOAA's GOES-19 satellite reveal colder cloud tops and deep convection near the center — signs of a strengthening system feeding on warm ocean waters.

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

Reports from NOAA and Air Force Reserve Hurricane Hunter aircraft indicate that maximum sustained winds have increased to near 75 mph. Steady to rapid strengthening is expected during the next two to three days, and Erin is forecast to become a major hurricane this weekend.

Erin strengthened into a Category 1 hurricane on Friday morning east of the Caribbean Islands and is expected to keep strengthening through the weekend.

Hurricane Erin formed Friday in the Atlantic Ocean on track to bring heavy rains that could lead to flooding and landslides in Puerto Rico and the Virgin Islands, forecasters said.