Tropical Storm Erin is forecast to strengthen into the first hurricane of the Atlantic season by Saturday morning and then become a major Category 3 hurricane by Sunday morning as it passes north of Puerto Rico. But as of now, Erin is not expected to pose a direct threat to the U.S.

As of the latest update, issued at 4 a.m. CDT Thursday, Tropical Storm Erin was located about 990 miles east of the Leeward Islands and was on a path to the west at 17 mph. (The next update will come later this morning, and updates will become more frequent once watches and warnings go into effect for the storm.)

Tropical Storm Erin is on track to begin strengthening in the next day or so, likely to hurricane status as soon as Friday. The National Hurricane Center’s latest forecast keeps the storm north of Puerto Rico and the Virgin Islands,