Hurricane Ernesto was downgraded to a tropical storm after making landfall in Mexico's Yucatan Peninsula, where it is dumping heavy rains, the U.S. National Hurricane Center, or NHC, said Wednesday.

The storm made landfall Tuesday night near Mahahual, a city in the southeastern state of Quintana Roo, as a Category 1 hurricane packing winds of up to 165 kph (103 mph), the Mexican weather service said.

Tropical Storm Ernesto was located about 145 kilometers (90 miles) south-southeast of Campeche, Mexico, at 1200 GMT, the NHC said.

The storm, which has maximum sustained winds of 95 kph (60 mph), is moving west at 24 kph (15 mph), the NHC said.

A hurricane warning is in effect from Barra de Nautla to Coatzacoalcos, Mexico.

A tropical storm warning is in effect from Chetumal, the capital of Quintana Roo state, to Tulum on the east coast of the Yucatan Peninsula and from Celestun south and westward to Coatzacoalcos along the Mexican Gulf coast, and from north of Barra de Nautla to Tuxpan, the NHC said.

Tropical Storm Ernesto is expected to weaken further as it moves over land Wednesday morning, but it is expected to regain strength when it emerges over the Bay of Campeche and could regain hurricane strength on Thursday, the NHC said.

Officials in Quintana Roo declared a state of alert Tuesday in the cities of Othon P. Blanco, Bacalar, Jose Maria Morelos, Felipe Carrillo Puerto and Tulum, telling residents to closely monitor the situation, the state emergency management office said.

An emergency plan is in place to assist and evacuate the nearly 1,700 tourists in the area if necessary, the state Tourism Secretariat said.

A total of 237 storm shelters with a capacity of 82,975 people were ready for use as the storm approached, Quintana Roo state officials said.

Quintana Roo is home to most of the tourist destinations in the Yucatan Peninsula.

Evacuations of coastal fishing communities in the southern part of the state, including Xcalak, Punta Allen, Banco Chinchorro and Mahahual were ordered on Monday night, state officials said.

Nearly 1,000 people were in shelters as of noon Tuesday, state officials said.

Operations at the Chetumal airport were suspended at 5:00 p.m. on Tuesday and the facility will remain closed until further notice.

Quintana Roo, Yucatan, Campeche, Chiapas and Tabasco states are the areas most likely to be affected by the heavy rains from Tropical Storm Ernesto, the national emergency management office said.

A total of 1,050 army troops have been placed on alert to assist local officials, the Defense Secretariat said.

Ernesto is the fifth tropical cyclone of the 2012 Atlantic season, following Alberto, Beryl, Chris and Debby, which killed three people in the United States.

The season officially began on June 1 and ends on Nov. 30, but two storms - Alberto and Beryl - formed in May. EFE