Tropical Storm Erin has begun strengthening as it streaks west across the Atlantic and is on track to reach hurricane status as soon as Friday, prompting tropical storm watches in the northern Leeward Islands.

Hurricane Erin strengthened rapidly to a Category 3 storm early Saturday as it churned towards the Caribbean, with a warning issued that flash floods and landslides were possible.

Hurricane Erin rapidly strengthened offshore to a “catastrophic” Category 5 storm on Saturday, as rain lashed Caribbean islands and weather officials warned of possible flash floods and landslides.