Hurricane Erin restrengthened into a Category 4 storm late Sunday, with forecasters warning it is expected to intensify and grow in size in the coming days as it lashes Caribbean islands with heavy rains that could cause flash floods and landslides.

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.

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.