A westward-moving tropical wave could produce an area of low pressure in the tropical Atlantic late in the week of Aug. 18, the hurricane center said on Aug. 16. The center shows a 20% chance of storm formation over the next week.

Hurricane Erin strengthened into a fearsome Category 5 hurricane with sustained winds of 160 mph for much of the day on Aug. 16 as it traveled west just north of the Virgin Islands, according to the National Hurricane Center.

It quickly powered up from a tropical storm to a Category 5 in a single day, the National Hurricane Center said.