Tropical Storm Milton, currently churning in the western Gulf of Mexico, was "forecast to strengthen into a major hurricane as it moves toward Florida into midweek next week," the National Weather Service said on social media platform X.

Depending on its path, Milton could potentially bring fresh havoc to areas of Florida's west coast still recovering from Helene, which roared ashore on September 26 as a powerful Category 4 hurricane with wind speeds of 140 miles (225 kilometers) per hour.

Helene moved inland up through Georgia, South Carolina and North Carolina, bringing historic flooding and killing at least 220 people, according to an AFP tally of official announcements.

In Florida, where Helene left at least 14 dead, Governor Ron DeSantis on Saturday said he had declared a new state of emergency in 35 counties ahead of Milton's arrival.

"We will continue staging state assets to prepare for efficient search and rescue, power restoration, and roadway clearing," he said on X.

"Steady to rapid strengthening is forecast during the next few days," the National Hurricane Center said Saturday.

Researchers say climate change likely plays a role in the rapid intensification of storms, because there is more energy in a warmer ocean for them to feed on.

Early forecasts showed Milton likely crossing over Florida into the Atlantic Ocean, with the NHC warning of potential "life-threatening impacts to portions of the west coast of Florida Tuesday or Wednesday."

That path would potentially spare the inland areas, such as the mountains of North Carolina, where Helene caused severe destruction from flooding.

With just weeks to go until election day -- and hard-hit Georgia and North Carolina likely to play a key role in deciding the presidential outcome -- Helene recovery efforts have become a political flashpoint.

Republican candidate Donald Trump has repeatedly spread misinformation about the federal response, falsely alleging that funding for relief has been misappropriated and redirected towards migrants.

The White House on Saturday slammed "scam artists, bad-faith actors, and others who want to sow chaos because they think it helps their political interests" for spreading false information.

"This is wrong, dangerous, and it must stop immediately," communications director Ben LaBolt and digital strategy director Christian Tom said in a statement.

Meanwhile Vice President Kamala Harris, the Democratic nominee, visited North Carolina on Saturday to receive a briefing and announce fresh funding to restore a key highway.