UPDATE 7-Ida becomes hurricane again in northwest Caribbean

* Storm Ida becomes hurricane for second time

* Mexico issues hurricane watch for parts of Yucatan

* Ida seen entering energy-rich Gulf of Mexico Sunday (Updates storm becoming hurricane)

MEXICO CITY, Nov 7 (Reuters) - Tropical Storm Ida became a Category 1 hurricane again late on Saturday in the northwestern Caribbean off Mexico's Yucatan Peninsula, the U.S. National Hurricane Center said.

The Miami-based hurricane center said Ida, which first became a hurricane on Thursday off the Caribbean coast of Nicaragua before weakening over that country, reached maximum sustained winds of about 75 miles per hour (120 kph), and was about 120 miles (195 km) east-southeast of Cozumel, Mexico.

Tropical storms become hurricanes when top sustained winds reach 74 mph (119 kph).

Forecasters expected the storm to weaken as it moves into the Gulf of Mexico next week.

Skies were sunny and clear on Saturday in the Mexican resort of Cancun, and Ida is expected to pass east of the city on Sunday afternoon.

Mexico issued a hurricane watch for the Yucatan Peninsula from the resort of Tulum to Cabo Catoche, north of Cancun.