(MIAMI) — A strengthening Tropical Storm Zeta is expected to become a hurricane Monday as it heads toward the eastern end of Mexico’s resort-dotted Yucatan Peninsula and then likely move on for a possible landfall on the central U.S. Gulf Coast at midweek. Zeta, which on Sunday became the earliest ever 27th named storm of the Atlantic season, was centered about 260 miles (420 kilometers) southeast of Cozumel island late Sunday, the U.S.