Five days after he was swept out to sea by a fierce current, the body of a 4-year-old boy was found Monday about 30 miles north of where he had gone in. He wasn’t even swimming when tragedy struck, officials say.

The boy and his mother were walking on the beach during the late afternoon on their Outer Banks vacation. A wave knocked them off their feet, and a current pulled the boy out to sea. As the waves continued to come in, his mother “lost sight of him in the surf,” according to the U.S. Coast Guard.

“A tragic accident occurred today in Kitty Hawk,” Chief Joel C. Johnson, of the Kitty Hawk Police Department, wrote in a Facebook post last week, explaining that the accident occurred under “the watchful eye of the attending parents while walking along the shore.”

Rip currents can form anytime, and they’re almost always present in some form. Stronger waves lead to stronger rip currents. The water piles up with each successive wave, and, with nowhere else to go, it moves horizontally along the beach until it reaches a weakness in the incoming waves. The force of the water flowing back out to the ocean overpowers the waves in this location, and a rip current is established. There can be numerous rip currents along the same beach.

Even an average rip current moves dangerously fast — one to two feet per second. On a strong rip current day, even a good swimmer could be carried out of reach in just seconds. Rip currents are thought to cause more than 100 drownings a year in the United States, and they’re the cause of 80 percent of all lifeguard rescues, according to the United States Lifesaving Association.

On the day the 4-year-old was pulled out to sea, the weather was warm and sunny, but the ocean was rough. A strong rip current advisory was in effect at the time, according to the National Weather Service, which is not uncommon in the Outer Banks — especially right after a storm. A cold front had just moved through the region and churned up the water. Waves were four to six feet high, according to the Coast Guard, and rip currents were strong.

“It’s always a danger near the ocean,” said Jeremy Thomas, chief petty officer with the U.S. Coast Guard in Wilmington, in an interview with The Washington Post last week. “It’s just a tragic case. No one wants to see something like this happen.”

3 things you must know about rip currents

You can check the rip current forecast for any location

The first thing you should do before going to the beach is to check the rip current forecast. The National Weather Service issues low, moderate and high risk advisories for rip currents, and they’re usually issued before the rip currents start. Mostly, the rip current statements are in the Hazardous Weather Outlook for the location. If it’s a particularly bad day for rip currents, the National Weather Service will issue a Beach Hazards Statement. Search for your city and state on weather.gov to find these statements.

Low risk — Life threatening rip currents often occur in the vicinity of inlets, groins, jetties and piers. Always supervise those who cannot swim and remember to heed the advice of the local beach patrol and flag warning systems.
Moderate risk — Swim near a lifeguard. Remember to heed the advice of the local beach patrol and flag warning systems.
High risk — The surf is dangerous for all levels of swimmers. Remember to heed the advice of the local beach patrol and flag warning systems.

The Weather Service also started offering a special beach forecast for the Outer Banks. Here you’ll be able to see exactly where there’s a risk of rip currents from low to high.

If you get to the beach without checking the forecast, you should try to spot the flags on the beach. In many coastal states, lifeguards use these flags to indicate the water conditions. A yellow flag indicates rip currents are present, and you should be cautious. A red flag means rip currents are present, and they are very strong. If you see a double red flag, don’t go in the water.

Know what a rip current looks like 

Rip currents may be hard to spot if you’re not paying attention, but they aren’t invisible — you just have to know what they look like.

Because a rip current is where the water is flowing away from the beach, they won’t have waves breaking in them. Look for areas where there’s a gap in the wave break or where there’s a trail of dark or muddy water. It also might look like a river of foam, as the foamy beach water is being drawn away from the shore. These are clear indicators of water flowing back out to sea.

If you get caught in a rip, swim parallel to the shore until you’re out

Swimmers often struggle against the force of the current trying to swim back, expending a lot of their energy. If you’re ever caught in a rip current, swim parallel to shore until you’re out of it, and then you can swim back to the beach. Wave your hands around to alert lifeguards that you are struggling.