The US state of Florida is preparing for the dangerous hurricane "Ian", which has already caused great destruction in Cuba.

"Predictions can change, but for now, experts are saying this could be a very severe hurricane, life-threatening and with devastating effects," US President Joe Biden said on Tuesday (local time).

The US hurricane center warned of a life-threatening storm surge and hurricane gusts on the west coast of Florida.

Evacuation instructions applied to 2.5 million people - numerous people got to safety.

"Ian" is expected to hit land on Wednesday evening (local time).

The cyclone made its way toward the Florida coast on Tuesday evening (local time) as a Category 3 of 5 hurricane.

Meteorologists warned that "Ian" will gain strength over the warm Gulf of Mexico and could reach sustained winds of more than 200 kilometers per hour.

The hurricane is expected to weaken before making landfall south of the city of Tampa, Florida Gov. Ron DeSantis said.

But because it then moves at a "snail's pace", a lot of rain will fall in the coastal region.

DeSantis called on people to protect themselves.

No one should assume that things will turn out lightly again this time, because that has often been the case in the past.

Houses can be rebuilt - but personal safety takes precedence over everything.

"You still have some time, but that time is running out fast," DeSantis said.

The region expected to be affected by the storm has not experienced such a hurricane for around 100 years, warned Deanne Criswell of the American Disaster Management Agency Fema.

It's important that even people who haven't lived in the southeastern state long and have little experience with hurricanes take the matter seriously.

Experts are also worried that in the past few decades, construction in the region has been getting closer and closer to the water.

Floods could damage or destroy many buildings.

Flooding and tornadoes are also to be expected in the interior of the country, the weather service said.

The US Department of Defense said more than 3,200 members of the Florida National Guard have been activated, with another 1,800 standing by if needed.

Florida has positioned soldiers, air force personnel and equipment at bases across the state in preparation for deployment to storm-hit areas, a department spokesman said in Washington.

For example, the National Guard can clear streets and help with search and rescue operations.

Disney announced it would be closing its Orlando theme parks and water parks on Wednesday and Thursday as a precaution.

Other recreational facilities, numerous shops and schools in Florida should also remain closed.

In the capital, Washington, Ian also messed up the political schedule.

A public hearing by the investigative committee into the Capitol attack scheduled for Wednesday has been postponed.