The storm will remain a major hurricane through the middle of the week, according to the National Hurricane Center.

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.

The outer bands of powerful Hurricane Erin lashed Puerto Rico, and the storm is approaching the Bahamas next. What can the mainland U.S. expect?

The first Atlantic hurricane of the season is forecast to bring heavy rain and life-threatening surf and rip currents to the U.S. East Coast this week.

Storms that ramp up so quickly complicate forecasting and make it harder for government agencies to plan for emergencies. Hurricane Erick, a Pacific storm that made landfall June 19 in Oaxaca, Mexico, also strengthened rapidly, doubling in intensity in less than a day.

While a Gulf disturbance that moved into Texas on Friday seems to have run its course, Hurricane Erin in the western Atlantic intensifies.

Erin briefly strengthened into a 'catastrophic' Category 5 storm before its windspeeds weakened. However, the Category 3 Hurricane will still bring heavy rains.

Tropical Storm Erin is approaching Puerto Rico and the Virgin Islands, bringing heavy rains that could cause flooding and landslides

There is a risk for dangerous surf and life-threatening rip currents along the entire east coast, including most of Florida.