TULUM, Mexico – Tens of thousands of tourists fled the beaches of the Mayan Riviera on Monday as monstrous Hurricane Dean roared toward the ancient ruins and modern oil installations of the Yucatan Peninsula.

Mexico’s state oil company, Petroleos de Mexico, said it was evacuating all of its more than 14,000 offshore workers in the southern Gulf of Mexico, which includes the giant Cantarell oil field.

Cancun seemed likely to be spared a direct hit, but visitors abandoned its swank hotels to swarm outbound flights. Officials evacuated more rustic lodgings farther south, where Dean was expected to smash ashore early Tuesday.

Dean already had winds of 150 mph as it brushed past the Cayman Islands on Monday, but the U.S. National Hurricane Center said the storm could grow even stronger – into a giant Category 5 hurricane – before striking Mexico. At 2 p.m. EDT, Dean was centered 330 miles east of Belize City, where authorities closed all hospitals and urged residents to leave.

The storm – which killed at least 10 people across the Caribbean – was expected to slash across the Yucatan and emerge in the Gulf of Campeche, where Petroleos de Mexico decided Monday to shut down production on the offshore rigs that extract most of the nation’s oil.

Shutting the 407 oil wells in the Campeche Sound will result in a production loss of 2.7 million barrels of oil and 2.6 billion cubic feet of natural gas a day, Pemex said. Of that, about 1.7 million barrels of oil a day is exported from three Gulf ports, where Pemex was loading the final tankers Monday morning before shutting them as well.

Central Mexico was next on the storm’s path, though the outer bands were likely to bring rain and gusty winds to south Texas, already saturated after an unusually rainy summer.

At the southern tip of Texas, officials urged residents to evacuate ahead of the storm. “Our mission is very simple. It’s to get people out of the kill zone, to get people out of the danger area, which is the coastline of Texas,” said Johnny Cavazos, Cameron County’s chief emergency director.