After briefly weakening, Hurricane Erin has re-intensified into a Category 4 hurricane with sustained winds of 130 mph, according to the National Hurricane Center.

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.

Erin reintensifies to a Category 4 hurricane and is likely to create dangerous surf along the U.S. East Coast this week.

SAN JUAN, Puerto Rico (AP) — Erin strengthened into a powerful Category 4 hurricane in the Caribbean on Saturday and continues to intensify, the National Hurricane Center said. The storm is 150 miles northeast of Anguilla with maximum sustained winds of 145 mph. It is moving west-northwest at 20 mph (31 kph).

Charley roared ashore near Cayo Costa, Florida, or west of Fort Myers, packing maximum sustained winds of 150 mph on the afternoon of Aug. 13, 2004. The intensification of Charley prior to landfall was a worst-case scenario since nearly eight hours earlier over the eastern Gulf, it was a Category 2 with 110 mph winds.