MIAMI (CBSMiami) – South Florida’s coastlines are under assault again as waves, surge and surf threaten to overwhelm our beaches and low lying coastal cities.

The National Weather Service said a large long period of northeast swells will continue to build Sunday and peak Sunday night in Monday morning. Seas of seven feet or greater are expected through at least Monday, highest off the northern Palm Beach coast Sunday afternoon and night with occasional seas up to 15 feet.

The seas over the rest of the Atlantic waters will also continue to build to 6 to 9 feet Sunday.

This will create dangerous breaking waves in the surf zone and potentially hazardous rip currents.

Large breaking waves on our shores could cause beach erosion and minor coastal flooding. The greatest impacts will be along Palm Beach County and northern Broward County beaches at during high tide periods.