Parts of Florida's Gulf Coast are now under a hurricane warning as the storm strengthens

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A storm system in the Caribbean Sea was officially declared Tropical Storm Helene late Tuesday morning and is expected to strengthen into a major hurricane by the time it reaches Florida's Gulf Coast on Thursday, the National Hurricane Center warned.

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Did Helene trigger evacuation orders in Florida?

Yes. Just before 5 p.m. EDT Tuesday evening, the Florida Division of Emergency Management said mandatory and voluntary evacuation orders had been issued in 13 counties. Six counties had mandatory evacuation orders: Charlotte County, Franklin County, Gulf County, Manatee County, Pinellas County and Wakulla County. Nearly the entire state is under a state of emergency.

Does Helene have an impact on airlines?

Airlines including United Airlines, Delta, JetBlue, Southwest and Frontier have issued travel advisories due to the storm and are allowing potentially affected passengers to rebook their plans free of charge.

What you should pay attention to

Meteorologists warn that the effects of Helene could be felt far inland due to an unusually large wind field and heavy rainfall. There is “a risk of landslides in the southern Appalachians.”

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“The entire west coast of the Florida Peninsula and the Florida Big Bend is under a threat of life-threatening storm surge,” the National Hurricane Center said Tuesday. “The highest flood levels are expected along the coast of the Florida Big Bend. Residents in these areas should follow the advice of local authorities and evacuate when instructed to do so.”

Important background

Helene is the eighth named tropical storm of the Atlantic hurricane season and comes weeks after Francine made landfall in Louisiana on Sept. 11 as a Category 2. The only tropical storm that formed between the two, named Gordon, lost strength in the Atlantic on Friday. Meteorologists predicted this year the strongest storm season (from June 1 to Nov. 30) the National Oceanic and Atmospheric Administration has ever forecast — as many as 25 named storms and 13 hurricanes — but the season so far has not been as active as predicted.

More information

ForbesHurricane Helene: Airlines issue travel warnings as storm heads toward FloridaFrom Suzanne Rowan KelleherForbesGovernment meteorologists issue the gloomiest hurricane season forecast in history – here's whyFrom Brian BushardForbesHurricane Francine reaches Louisiana as Category 2From Mary Whitfill Roeloffs