Hurricane Melissa strengthened into a Category 5 storm overnight and is expected to bring "catastrophic and life-threatening winds, flooding and storm surge" to Jamaica, forecasters say.

Hurricane Melissa intensified to Category 5 strength Monday as it neared Jamaica with up to 30 inches (76 centimetres) of rain and a life-threatening storm surge.

Widespread damage to property and infrastructure is expected and some were already in storm shelters Sunday Night.