The Outer Banks in North Carolina are under evacuation warning as Hurricane Erin whips up potentially 20-foot high waves and flooding along the east coast.

Additional strengthening is expected as the storm is forecast to “remain a large and dangerous major hurricane through the middle of this week,” the National Hurricane Center said.

In recent decades, the Atlantic has been warming at record rates, helping hurricanes explode into powerhouses.

Hurricane Erin has undergone a period of astonishingly rapid intensification — a phenomenon that has become far more common in recent years as the planet warms. It was a rare Category 5 on Saturday before weakening,

Hurricane Erin has been downgraded to a Category 3 hurricane. A tropical storm warning is in effect for the Turks and Caicos Islands as winds and heavy rains continue to lash the Virgin Islands and Puerto Rico.

Rip currents are the third leading cause of deaths from hurricanes, and they can happen on a sunny day hundreds of miles from the storm.

After exploding in strength at a historic rate this weekend, Hurricane Erin is now a sprawling Category 4 storm churning in the Atlantic. The storm’s enormous footprint is becoming the biggest concern as it threatens to drive life-threatening rip currents and towering waves toward the eastern US coastline and Bermuda.

The storm will remain a major hurricane through the middle of the week, according to the National Hurricane Center.