MEXICO CITY (Reuters) - Arlene, the first tropical storm of the Atlantic hurricane season, is strengthening and is likely to make landfall along Mexico's northeastern coast early on Thursday, threatening an oil refinery but likely sparing the country's offshore platforms from a direct hit.
The storm had maximum sustained winds of 50 mph and was located about 155 miles east of Tampico on Wednesday morning, the U.S. National Hurricane Center said. Winds were likely to reach hurricane strength.
"The official intensity forecast ... now shows Arlene approaching hurricane strength at landfall," the NHC said in a statement.
The center's model showed Arlene making landfall in Tampico, Tamaulipas state, where a Pemex refinery produces 190,000 barrels per day.
Mexico is a top oil exporter to the United States and almost all of its exports are shipped to refineries on the U.S. Gulf Coast from the three Gulf of Mexico ports, Dos Bocas, Cayo Arcas and Coatzacoalcos.
The center's model showed Arlene hitting north of the ports, but rains and winds from the storm may reach refineries in Tula and Salamanca, which are in the center of the country just north of Mexico City.
Major offshore oil fields are not in the storm's path.
Arlene is expected to produce rainfall over the eastern Mexican states of Tamaulipas, Veracruz and eastern San Luis Potosi.
"These rains could cause life-threatening flash floods and mudslides," the NHC said.
The area, prone to flooding, is popular with local tourists for its beaches and many poor coastal towns lack flood defenses. A hurricane warning is in place along the coast from Tuxpan northward to La Cruz.
The rain could bring some relief to sorghum and fruit farms in the area, however, after a long dry spell that has reached critical levels in some areas of Tamaulipas and in neighboring Nuevo Leon.
Mexico was hit by Hurricane Beatriz, the second tropical storm of the Pacific season, last week but the weather system did no major damage.
(Reporting by Elinor Comlay in Mexico City, additional reporting by Naveed Anjum and Koustav Samanta in Bangalore; editing by Philip Barbara)
