Florida orders new evacuations as Hurricane Milton strengthens

Survivors of deadly Hurricane Helene along the Florida coast were ordered to evacuate again as authorities warned another major storm was building into a Category 3 and would cause "devastating damage".

Relief workers in the area are still racing to find survivors in the aftermath of Helene, which killed more than 225 people across a handful of states.

Storm surge warnings were issued once again for parts of Florida as Milton, currently a Category 1, approached with winds of 161 kilometres an hour, the US National Hurricane Center said in its latest advisory on Monday.

Tampa Mayor Jane Castor told CNN that the city was "still cleaning up from Helene" and that the rain from the new storm would be "difficult enough, not to mention the storm surge and wind damage."

Milton "is forecast to intensify rapidly and become a major hurricane later today," and was expected to hit Florida's west coast on Wednesday, the NHC said.

Major hurricanes — categories 3 and above — carry minimum wind speeds of 178 kilometres an hour, according to the NHC, which warns "devastating damage will occur" to even well-built homes, while "electricity and water will be unavailable for several days to weeks after the storm passes."

Florida Governor Ron DeSantis has declared 51 of the state's 67 counties under a state of emergency, predicting Milton could have "major, major impacts."

President Joe Biden was briefed on Milton and said in a statement his administration was readying "life-saving resources."

Milton is forecast to move north of the Yucatan Peninsula and across the southern Gulf of Mexico Monday and Tuesday, the NHC said.

Its storm surge will "raise water levels by as much as 0.6 to 1.2 metres above ground level" along the northern Yucatan coast and cause "large and destructive waves," it said on Monday.

Aftermath of Hurricane Helene

Hurricane Helene hit the Florida coastline as a Category 4 storm, dumping torrential rainfall and causing flash flooding in remote towns in states such as North Carolina.

The storm, which struck Florida on September 26, was the deadliest natural disaster to hit the United States since 2005's Hurricane Katrina — with the death toll still rising.

Communities, particularly those in remote mountainous areas, have been left without power and drinking water.