Storms that ramp up so quickly complicate forecasting and make it harder for government agencies to plan for emergencies. Hurricane Erick, a Pacific storm that made landfall June 19 in Oaxaca, Mexico, also strengthened rapidly, doubling in intensity in less than a day.

A video shared from San Juan, Puerto Rico, shows the city starting to feel the effects of Hurricane Erin on Saturday, Aug. 16.

Hurricane Erin has exploded into a Category 5 hurricane in the Caribbean, according to the National Hurricane Center. The storm is currently north of Anguilla, with winds of 160 mph.

Hurricane Erin has been downgraded to a Category 3 hurricane but is gaining in size and raising the risk of life-threatening surf later this week along the U.S.

As of 5:00 p.m. AST on Sunday, Erin’s center was positioned approximately 275 miles northwest of San Juan, Puerto Rico, tracking west-northwest at 13 mph. Although no longer directly affecting the area, the storm’s outer bands are still delivering heavy rainfall, dangerous marine conditions, and life-threatening surf along coastal areas.

U.S. shores are unlikely to see a direct hit, but a strong offshore hurricane can produce massive and dangerous waves well away from its center.

Forecasters said Erin should begin to slowly weaken as it increased wind shear. However, it's predicted to remain a major hurricane until late next week.

While the category 4 storm is not expected to make landfall on the U.S. east coast, it will have an impact nonetheless. Dangerous high surf and rip currents are expected from Florida to New England throughout the week.