Do You Know How To Spot A Rip Current?

The ocean can look calm, inviting and even harmless. But just beneath that postcard-perfect surface, there’s a force that can quietly pull even strong swimmers away from shore in seconds.

They’re called rip currents, and understanding how they form, how to spot them and what to do if caught in one could save your life.

Let’s start with the basics.

Rip currents are powerful channels of flowing water that move offshore. "They can form along any coastline, east or west coast as well as the Great Lakes," explains meteorologist Caitlin Kaiser. "Anywhere where we have breaking waves.”

So how do they form? Picture waves steadily pushing water toward the shore. That water has to go somewhere, and when it builds up, it looks for the easiest way back out.

“The path of least resistance is through a small break in the sandbar,” Kaiser says. “So as it flows back through the sandbar, that’s where it picks up speed and causes the rip current.”

(MORE: The Coast Guard’s Must-Know Boating Safety Tips)

Typical rip current speeds are about 1 to 2 feet per second, but they’ve been clocked as fast as 8 feet per second, which is “faster than an Olympic swimmer,” Kaiser notes. That’s why trying to outswim one directly back to shore often doesn’t work.

Certain conditions make rip currents more likely. Wave heights of 2 to 3 feet or higher, strong onshore winds and even low tide can all set the stage.

And here’s something that surprises a lot of people: storms don’t have to be nearby. “Distant hurricanes can actually cause rip currents thousands of miles away,” Kaiser says, sending long-range swells toward otherwise sunny beaches.

(MORE: Hidden Dangers Lurk Miles From The Storm)

That’s part of what makes rip currents so dangerous: They don’t always look dangerous, often forming on otherwise bright, beautiful days when the water seems calm.

If you’re standing on the shore, there are a few clues to watch for. From a slightly elevated view, you might spot:

• A section of water that looks either unusually calm or extra choppy compared to the surrounding waves
• Water that appears darker or muddier, thanks to sand and sediment being pulled offshore
• Foam or seaweed streaming steadily away from the beach in a narrow line

Despite these warning signs, rip currents remain a leading beach hazard. More than 100 people die each year because of them, and they account for more than 80% of lifeguard rescues.

(MORE: The Most Important Life Jacket Tips)

So what should you do if you get caught in one?

First (and most important), don’t panic. “They will pull you out to sea but not under. That’s a common misconception,” Kaiser says.

Instead of fighting the current head-on, try to swim parallel to the shoreline until you’re out of the narrow channel, then angle back toward land. If you’re too tired to swim, float on your back, wave your arms and call for help.

The best defense, though, is preparation.

Always swim at beaches with lifeguards when possible, and check both the beach and wave forecasts before heading out. The National Weather Service issues rip current risk levels (low, medium and high) to help beachgoers gauge the danger.