Tropical Storm Erin has formed on a path toward the Caribbean and is expected to strengthen to a hurricane later in the week as it passes by Puerto Rico. Most models forecast the storm turning upward into the Atlantic Ocean, but a few see the storm continuing onward to the U.S. mainland.

Tropical Storm Erin, still far in the east-central Atlantic, is forecast to intensify into a major Category 3 hurricane by this weekend, but a big turn to the north is still expected before the