The key to the severity of impacts in the Leeward Islands and Puerto Rico from strengthening Erin depends on how soon a turn to the northwest occurs with a near-miss versus a direct hit.

Tropical Storm Erin is nearly at hurricane strength Thursday night, its western path putting islands in the far eastern Caribbean under tropical storm watches, according to the National Hurricane

Tropical Storm Erin is tracking quickly westward through the open Atlantic waters and should become increasingly organized in the coming days, potentially reaching major hurricane intensity this weekend as it tracks just north of the Caribbean islands, where it could bring rain and gusty winds.