RED FLAGS: The most serious of all beach warning flags, red flags warn swimmers of serious hazards in the water.
One red flag means that the surf is high or there are dangerous currents, or both. It means that the water is closed to swimming, as conditions are too dangerous for even the strongest swimmers.
Yellow Flags: When ocean conditions are rough, but not life-threatening, you might see a yellow flag on the beach. A yellow flag indicates potentially high surf or dangerous currents and undertows, and means that swimmers should exercise extreme caution. If there is a yellow flag, swim only near lifeguards and heed all lifeguard warnings.
If you’re swimming with children, or you aren’t a strong swimmer yourself, wear a life jacket when swimming on yellow-flag days. Some beaches have a permanent yellow flag because of rocks, a sudden drop-off or a high population of bait fish that attracts predators.
Green Flags: The ocean is always unpredictable and even on clear and calm days, hazards still exist. Still, there are days when the threat of danger is lower than others. A green flag on the beach is an all-clear sign, indicating that it’s safe to swim.
Even when the flag is green, though, exercise caution in the ocean, listen to lifeguard warnings and keep a close eye on children.