Mexico ? Tropical Storm Karl dumped heavy rains on the Yucatan Peninsula today as it moved toward the Gulf of Mexico, where it is expected to pick up steam and become a hurricane threatening Mexico’s central coast by the weekend.

In the Atlantic, forecasters say Hurricane Igor has spun into a major Category 4 storm and is threatening to generate life-threatening rip currents along the U.S. East Coast over the weekend and to bring large swells to the Bahamas and Virgin Islands before that. Category 3 Hurricane Julia is not a threat to land.

In Mexico, the government issued a hurricane watch for its eastern Gulf Coast. It is expected to reach the coast on Saturday.