Beachgoers warned of dangerous rip currents at New Jersey and Delaware shores

If you're heading to the beach this weekend, be careful in the water.

Forecasters are warning of dangerous rip currents at beaches in New Jersey and Delaware.

There will be heavy swells all along the East Coast because of Hurricane Ernesto , which is churning out in the Atlantic.

As of Friday morning, Ernesto was a Category 2 storm with maximum sustained winds of 100 mph.

Ernesto was expected to strengthen further on Friday before it passes near or over Bermuda on Saturday.

Here's what you need to know about rip currents:

1. Rip currents aren't just dangerous -- they can be deadly . The phenomenon accounts for about 100 deaths every year at U.S. beaches.