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.

At 2 AM AST, Erin’s maximum winds have dropped to 125 mph, taking the storm back to a Category 3 hurricane. The center is 140 miles of San Juan Puerto Rico, advancing west-northwest at 14 mph with a central pressure of 940 mb (millibars).

Hurricane Erin was expected to soak the Virgin Islands and Puerto Rico with heavy rain through the weekend before heading north up the Atlantic.

Over the weekend, northern portions of the Leeward Islands, the Virgin Islands, and Puerto Rico are expected to receive tropical rain ranging from 2 to 4 inches, with isolated totals up to 6 inches. Flash flooding, landslides and mudslides will be the main concerns over the next several days.