The National Hurricane Center's prediction cone shows a westward trajectory, but doesn't paint a clear picture whether or not it's likely to impact the east coast of the United States. Spaghetti models, which represent a collection of predicted paths generated by multiple computer models, paint a more definitive picture as of Wednesday morning.

Tropical Storm Erin is forecast to track close to Puerto Rico and Hispanola as a major Category 3 hurricane, but is likely to turn north before the U.S. coast.