Hurricane Idalia strengthens to Category 3 as it nears Florida

Hurricane Idalia has been upgraded to a Category 3 hurricane as it nears Florida, and is expected to strengthen further into a "catastrophic" Category 4 hurricane.

It is forecast to make landfall on Wednesday morning local time.

Potentially life-threatening conditions are forecast, including surging seawater up to 15ft (4.5m) above ground level in some areas.