CHETUMAL, Mexico (CNN) -- Hurricane Dean made landfall on Mexico's Yucatan coast Tuesday morning as a monster Category 5 storm -- capable of inflicting catastrophic damage -- after gaining intensity in the western Caribbean overnight.
Residents look at the waters in Chetumal, Mexico. Rain from the storm hit Monday. more photos »
The leading edge of Dean's eyewall moved ashore at about 4:30 a.m. Tuesday just north of Chetumal, the capital of the Mexican state of Quintana Roo, according to the latest advisory from the National Hurricane Center.
Dean's maximum sustained winds were 165 mph, and the center of the storm was about 35 miles east-northeast of Chetumal moving west-northwest at about 20 mph, according to the NHC's 4 a.m. (5 a.m. ET) advisory.
A Category 5 storm is the most extreme level on the Saffir-Simpson scale of hurricane intensity. Such hurricanes can have a storm surge of more than 18 feet and are powerful enough to take off roofs, uproot trees, blow out windows and even completely destroy some structures.
The area where the eye came ashore is rural and sparsely populated. However, hurricane force winds extended 60 miles from the center, and tropical storm conditions extended 175 miles.
Electricity was out in Chetumal, where most of the 130,000 residents in the coastal city appeared to have heeded government warnings to seek shelter or evacuate.
Further north, tourists fled popular resort areas such as Cancun and Cozumel, trying to get a seat on the last planes out before the storm. Of the 20,000 tourists in Quintana Roo, about 13,000 had been evacuated as of Monday evening, and planes were still taking off, said Rosario Ortiz Yeladaque, the state's secretary of government.
About 20,000 tourists remained in Cancun hotels. Security guards at the Gran Melia Hotel prevented guests and journalists from going outside into the storm by chaining and barricading exits, according to CNN's Jason Carroll. Watch I-Reporter Kevin Canning's video of Hurricane Dean in Belize »
Jeff Spiegel, owner of the Azul Resort in Amerbergris Caye, Belize, said it was "incredibly windy" and the ocean surge was "very, very high." Most of the docks and piers have been washed away on the western side of his narrow island, he said.
Dean is so large -- about the size of Texas -- that its tropical winds and waves were expected to affect the entire Yucatan and neighboring Belize to the south.
The Mexican government deployed 4,000 troops to the area, and a state of emergency was declared in the inland state of Campeche, where residents were bracing for as much as 20 inches of rain in some places. Watch I-Report images of Dean's effects on the Caribbean »
Mexican President Felipe Calderon, who was in Canada for a trilateral meeting with President Bush and Canadian Prime Minister Stephen Harper, announced he would cut short his visit and return home Tuesday to deal with the storm.
In anticipation of the storm, parts of Belize, including Belize City, were put under a curfew Monday night, and Prime Minister Said Musa froze prices of goods and services to prevent price gouging. People were being evacuated from low-lying, coastal and valley areas to hurricane shelters, the prime minister's office said in a statement.
Dean is forecast to weaken substantially as it crosses the Yucatan peninsula Tuesday, before re-emerging in the Gulf of Mexico, strengthening again and hitting central Mexico Wednesday with winds around 100 mph.
Forecasters do not believe it presents a threat to the United States, although officials in Texas continued to make storm preparations just in case Dean's path takes an unexpected turn.
Hurricane warnings were in effect for Belize and both the east coast of the Yucatan, facing the Caribbean, and the west coast, facing the Gulf of Mexico, which means hurricane conditions, including winds of at least 74 mph, were expected in those areas over the next 24 hours.
Along the northern Yucatan coast, winds were only expected to reach tropical storm force, above 39 mph. Mexican authorities also issued a hurricane watch for the country's western Gulf coast from the Bay of Campeche northward to Tampico, which means hurricane conditions were possible within 36 hours.
Meanwhile, in Jamaica, residents cleaned up fallen trees and debris Monday as the island nation started to recover from its brush with Dean on Sunday.
While electric service was still out and most stores were closed, the international airport in Montego Bay reopened Monday night, allowing tourists who had been caught in the storm to finally begin leaving.
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Although parts of Jamaica were pounded with sustained winds of 114 mph, the eye of the hurricane actually passed to the south of the island, sparing its 2.8 million residents from a direct hit. While the storm caused property damage and triggered landslides in some rural areas, no deaths were reported.
Dean is being blamed for at least seven deaths in its march across the Caribbean, including two fatalities in Haiti, two in both Martinique and Dominica and one in St. Lucia. E-mail to a friend
CNN's Susan Candiotti, Harris Whitbeck, Gary Tuchman, and Rob Marciano contributed to this report.
Copyright 2007 CNN. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed. Associated Press contributed to this report.
All About Hurricane Dean
Hurricane Dean satellite image as of 19:15 UTC on August 21, 2007.
After gaining strength in the western Caribbean last night,  made landfall as a Category 5 storm on Mexico's  at about 4:30 a.m. this morning (EDT). 

The storm struck just north of , the capital of the Mexican state of . However, hurricane-force winds were felt over 60 miles (~100 km) away from the center of the storm, and tropical storm conditions impacted areas 175 miles (280 km) away.

The Mexican government ordered the deployment of over 4,000 troops, and declared a state of emergency in the state of Campeche. Some areas braced for up to 20 inches (510 mm) of rain.

Dean made landfall as a category 5 storm, before being downgraded hours later to a category 3 storm. Later Tuesday afternoon, Dean was downgraded to a category 2 storm. Currently, the storm maintains category 1 status, with top sustained winds at 85 mph (137 km/h). 

The hurricane moved towards modern oil installations of the Yucatan Peninsula, prompting evacuations of offshore oil rigs that produce most of Mexico's oil and gas.

Forecasters warn the storm could pick up strength as it crosses the  and turn into an even more destructive hurricane before making a second landfall on Wednesday.

A hurricane warning remains in effect along the Gulf Coast of Mexico from south of Progreso to Tampico.

Forecasters do not believe it presents a threat to the United States.

Dean is being blamed for 13 deaths already.