An eyewall replacement cycle is underway within Hurricane Erin as the monster storm continues to barrel across the Atlantic while bringing gusty winds and rain to Puerto Rico and the Virgin Islands after rapidly intensifying into a catastrophic Category 5 hurricane over the weekend.

Offshore Hurricane Erin was downgraded to a Category 3 storm early Sunday, as rain lashed Caribbean islands and weather officials warned of possible flash floods and landslides.It also warned of "locally considerable flash and urban flooding,

Hurricane Erin pelted parts of the Caribbean and was forecast to create dangerous surf and rip currents along the U.S. East Coast this week.

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

Hurricane Erin, which briefly reached Category 5 strength, battered parts of the Caribbean, including Puerto Rico and the U.S. Virgin Islands, with heavy rain and strong surf. Though it won’t make landfall in the U.

Erin, the first hurricane of the season, is now forecast to become a Category 4 by Sunday. Here's where it could head in the week ahead.