Beach warning flags decoder

What beach warning flags mean

Many U.S. beaches fly colored flags to warn swimmers about the water that day. The National Weather Service describes the most common system like this (NWS Tallahassee (opens in a new tab)):

• Double red: the water is closed to the public. You could be arrested or fined for going in.
• Red: high hazard, with high surf and/or strong currents. The NWS recommends staying out of the water (opens in a new tab), because dangerous rip currents are expected, stronger and more often.
• Yellow: medium hazard, with moderate surf and/or currents. Be cautious if you go in, don't swim alone, and know what to do if you are caught in a rip current.
• Green: low hazard with calm conditions, but it's still wise to be careful.
• Purple: dangerous marine life, such as jellyfish. It can fly alongside the other flags and is not a rip current warning.

No flag is not a green flag

The National Weather Service says the absence of flags does not mean the water is safe (opens in a new tab). Flags are not used at every beach, and their meaning can vary from place to place (opens in a new tab). That is why the first step at any beach is to read the safety signs at the entrance, then look for flags near the lifeguard stand, and ask the lifeguard if anything is unclear.

Rip currents are the main reason flags go up. NOAA says rip currents can move at up to 8 feet per second (opens in a new tab), faster than an Olympic swimmer, and estimates that about 100 people are killed by rip currents in the U.S. each year. They also form on calm, sunny days, so good weather is not a safety signal.

The best protection: a lifeguard

The National Weather Service cites the U.S. Lifesaving Association's estimate that the chance of drowning at a beach with lifeguards on duty is 1 in 18 million (opens in a new tab). Swim near a lifeguard, check the beach forecast before you go, and keep young children within arm's reach even when the flag is green.

How to use this tool

Tap or select any flag to see what it means and what to do. Then try the practice round: you'll see a flag and choose what it means, with the answer explained each time. Practising before a trip helps children remember the colors. Nothing you choose leaves this device.

For more, read beach warning flags: what each color means, how to spot and escape a rip current and why swimming near a lifeguard matters.

What you can do today

1. Go through the flags with your family and do the practice round together.
2. Before your next beach day, check the National Weather Service surf zone forecast.
3. Learn what to do in a rip current with the rip current trainer.