MIAMI (CBS4) – Red and purple flags are flying at some lifeguard stands up and down South Florida’s beaches warning beachgoers of stinging jellyfish.

For the past couple of weeks, conditions have been favorable for jellyfish to arrive on the beaches of Broward, Miami-Dade and even the Florida Keys.

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Lt. Julio Diaz with Haulover Beach Ocean Rescue said they have  purple (dangerous marine life) flags flying at their stations.  Ft. Lauderdale has posted red (hazardous conditions) and purple flags.

“It’s kind of creepy,” said beachgoer Ryan Rauert, who had a close encounter.  “I walked out to the shoreline and stepped on a nice size jellyfish, the thing was about ya big and was red with tentacles,” he said.

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Monday, an off duty lifeguard paddled out into the middle of them.

“If you get in the water, you’re going to get stung,” warned Miami Dade Fire Ocean Resuce Lifeguard Grace Mangas.  “It’s kind of like getting red ant bites.”

The slimy sea creatures are pretty neat to look at, but you don’t want to get stung by one. While not a serious injury, jellyfish stings can be pretty painful. The stings cause itching, burning and rashes. Lifeguards usually have a vinegar solution on hand to neutralize the stinging. You can also wash the affected area with meat tenderizer.

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Portuguese man o’ war and cannonball jellyfish make relatively frequent appearances along Atlantic coast beaches but these are a different species, believed to be called moon jellyfish, also known as common jellyfish or saucer jellyfish. They are transparent and like other jellies, primarily drifts with the current, even when it is swimming.

Mangas said recent storms passing by possibly blew the jellyfish in – and the lack of wind – has kept them hanging around.

“Even though you may not see an active jelly, you may not see the animal itself, the tentacles can break off and they can sting you 24 to 48 hours they’re still alive,” she said.

Since Sunday, lifeguards have been letting people know what lurking around out there.  It turned the Contrerras family around.

“My mom saw a few but the lifeguard told us there were just tons of jellyfish, so not a good idea to go in,” said Jorge Contrerras.

For many, it means packing up – and making new plans for the day of fun in the water.

“So now we’re going to hit the swimming pool where there’s no creatures,” laughed Norma Fearns, as she packed her family up and left Fort Lauderdale Beach.

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Life guards will check the water in the morning to see if the jellyfish are still around.  That’s when they will decide whether to open to beach to swimmers.  Most other South Florida beaches have remained open, but warned of dangerous jellyfish.