Beach Safety Guide
A plain-English guide to South Florida beach flag colors, rip currents, and what each warning actually means.
This guide is informational only. The physical
flag at the lifeguard tower and any verbal advice from on-duty
lifeguards always take precedence over what you see in the app or
on this page.
Flag color reference
The Florida beach flag system follows the International Life Saving Federation standard, with a few additional colors used by some Florida counties.
Green — Low Hazard
Calm conditions, clear water, low surf, low rip current risk.
Swim with normal caution.
Yellow — Medium Hazard
Moderate surf and/or currents. Strong swimmers only beyond
knee-deep water. Children and weak swimmers should stay close
to shore.
Red — High Hazard
Dangerous surf, strong currents, or both. Most lifeguards will
ask everyone to stay out of waist-deep water. Rip currents are
likely.
Double Red — Water Closed
The water is closed to public swimming. Hazards may include
extremely high surf, lightning offshore, sewage spill, or
aggressive marine life. Do not enter the water.
Purple — Marine Pests
Stinging marine life present — typically jellyfish, Portuguese
man-of-war, or sea lice. The water may be physically safe to
enter but you'll likely be stung.
Blue — Dangerous Marine Life
Less common; used by some agencies for shark sightings or
dangerous animals other than stinging pests.
Orange — Air Quality
Smoke, dust, or other air hazard. Check with lifeguards before
extended exposure if you have respiratory conditions.
Black — Severe Weather
Lightning detected within 8 miles, severe weather approaching,
or other emergency closure. Leave the beach.
Rip currents
Rip currents are narrow, fast-flowing channels of water moving away from shore. They cause more drowning deaths in Florida every year than sharks, alligators, and hurricanes combined.
How to spot a rip current
- A channel of noticeably darker, calmer water between sections of breaking waves.
- A line of foam, seaweed, or debris moving steadily out to sea.
- A break in the wave pattern — waves crash on either side but not in the middle.
- A different color water (often sandier) moving offshore.
If you get caught in one
- Don't fight it. A rip current can move at 8 feet per second — faster than an Olympic swimmer. Swimming straight back to shore against it will exhaust you.
- Stay calm and float. The current will carry you out, but it won't pull you under.
- Swim parallel to the shore until you're out of the rip (usually 30–100 feet).
- Then swim diagonally back to shore.
- If you can't escape, wave one arm and yell for help.
If you see someone else caught
Do not swim out to rescue them. Most rip current drownings involve a would-be rescuer. Throw them anything that floats (cooler, boogie board, life ring) and call 911 or signal a lifeguard immediately.
Surf height — what the numbers mean
- 0–2 ft — Calm. Safe for all swimmers.
- 2–4 ft — Moderate. Manageable for confident swimmers; tiring for children.
- 4–6 ft — Rough. Strong swimmers only. Significant rip current risk.
- 6+ ft — Dangerous. Most beaches will fly red or double-red. Stay out of the water.
Marine life
South Florida's most common stinging hazards:
- Jellyfish (moon, sea nettle, etc.) — sting on contact. Rinse with seawater (never freshwater), remove tentacles carefully, apply vinegar if available.
- Portuguese man-of-war — not technically a jellyfish but produces similar painful stings. Tentacles can remain venomous for hours after the animal is dead. Stings are rarely fatal but can cause severe reactions; seek medical help if symptoms include difficulty breathing or chest pain.
- Sea lice (jellyfish larvae) — invisible microscopic stingers that get trapped under swimwear, causing an itchy red rash hours later. Rinse, change out of swimwear, wash in hot water.
- Stingrays — usually buried in shallow sand. Shuffle your feet when entering the water — “the stingray shuffle” — to alert them to move out of your way.
Sun and heat safety
- Florida UV index is 9-11+ most of the year. Use SPF 30+ sunscreen, reapply every 2 hours and after swimming.
- Drink water before you feel thirsty. Heat exhaustion creeps up fast.
- Watch for signs of heat illness: dizziness, headache, nausea, confusion. Get to shade, cool down, hydrate.
Lightning
30/30 rule: if you hear thunder within 30 seconds
of seeing lightning, leave the water and seek shelter for at
least 30 minutes after the last thunder. Lightning can strike up to
10 miles from a storm — it does not need to be raining at your
location.
When to swim
The safest time is when lifeguards are on duty (typically 9 AM to 5 PM, varies by beach). Never swim alone, at night, or after drinking.
Emergency contacts
- Life-threatening emergency: 911
- Florida Poison Control: 1-800-222-1222 (jellyfish stings, marine envenomation)
- National Weather Service Miami: weather.gov/mfl