Hurricane Michael could help move red tide off Treasure Coast | Map link to FWC results

While Hurricane Michael is bad news for Florida's Panhandle, it could bring good news on the red tide front to the Treasure Coast. 

Michael could cause winds along Florida's East Coast to shift from easterly, which has been bringing red tide onto shore, to southerly beginning late Tuesday morning.

More:Tropical Storm Michael: Impact on the Treasure Coast from the storm

"More southerly winds, plus the south-to-north movement of the Gulf Stream, could help move red tide out of our area," said Malcolm McFarland, a research associate at Harbor Branch Oceanographic Institute at Fort Pierce.

That's the good news. The not-so-good news is that October typically brings particularly high tides, known as "king tides," to Florida's East Coast, said Jessie Smith, a meteorologist at the National Weather Service in Melbourne.

More: Michael could affect West Coast red tide too

McFarland said he's concerned the "king tides" could help push "large populations" of red tide onto Treasure Coast beaches and possibly into the Indian River Lagoon via the St. Lucie Inlet.

"Once it gets into the lagoon, the red tide could get trapped," McFarland said, "and stick around a lot longer. I don't expect that, but it's a definite possibility."

A long-lasting red tide in the lagoon could lead to fish kills and the loss of other marine life, Zack Jud, education director at Florida Oceanographic Society in Stuart, told TCPalm last week.

More:Red tide, blue-green algae, Erin Brockovich, Lake Okeechobee discharges 

Not moving north ... for now

Testing by the Florida Fish and Wildlife Conservation Commission indicates the red tide hasn't expanded north along the Treasure Coast. 

More: Check out state red tide map

Here's a wrap-up of conditions along the Treasure Coast:

Martin County

• Low or very low red tide levels are reported along southern beaches (Blowing Rocks Preserve, Hobe Sound and Bathtub Beach), no red tide was found at Jensen Beach and Indian Riverside Park on the lagoon.
• Martin County beaches are open with lifeguards on duty and signs advising visitors of the possible presence of red tide. For daily updates, call 772-320-3112.

St. Lucie County

• Very low levels of red tide are reported at southern beaches (the Martin-St. Lucie county line, Waveland and Dollman beaches), with no red tide reported north of Dollman Beach.
• All St. Lucie County beaches are open. For daily updates, call 772-462-1421.

Indian River County

• Water was tested for the first time Wednesday, but no red tide found in the lagoon at Sebastian, near the mouth of the Sebastian River and at the Sebastian Inlet.

Occurs naturally, enhanced by runoff

Red tide is a type of marine algae (Karenia brevis) that occurs naturally, mostly on Florida's Gulf Coast and in smaller numbers on the Atlantic Coast without human influence. But runoff from fertilizer and leaky septic tanks can contribute to the red tide's growth.

Florida's West Coast has been plagued with red tide since October 2017, then it arrived in the Florida Keys in mid-September, then it hit the east coast in late September. 

The red tide cells apparently got caught in currents that moved it from the Gulf of Mexico, around the tip of Florida and up the East Coast via the Gulf Stream.

More: What is red tide? Here's what you need to know

Touching contaminated waters can cause rashes, especially for people with sensitive skin.

Airborne toxins from the algae can cause shortness of breath, coughing and scratchy throats. People with chronic lung conditions such as emphysema are at the greatest risk.