Meteorologists have been tracking the storm for the past week, with its chances of forming increasing gradually. Tropical Storm Sara is expected to form by Thursday morning, becoming a hurricane by Friday night and a major hurricane by Saturday night, AccuWeather said.

A hurricane watch means that hurricane conditions are possible within the watch area. A watch is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous.

The eventual path and strength of newly named Tropical Storm Sara remain uncertain Thursday, with forecasters closely monitoring each computer model run as the system spins in the Caribbean Sea near storm-vulnerable Central America, where a "catastrophic ...