Hurricane Barbara has hit Mexico's southern Pacific coast, flooding roads, toppling trees and killing at least two people before weakening to a tropical storm as it moved inland.
The US National Hurricane Center said on Thursday that the cyclone had forced hundreds of people to evacuate their homes in Oaxaca and Chiapis state.
The hurricane was churning north-northeast at about 15kph and should weaken rapidly overnight, the NHC said.
According to media reports, 14 fishermen disappeared in the state of Oaxaca during the storm. Local emergency services said they could not confirm that information.
Manuel Maza, director of emergency services in Oaxaca state, said that very strong winds and intense rainfall had hit the region and that power outages were reported.
Local emergency services said a 61-year-old US man surfing off the beach at Salina Cruz drowned during the storm. The second victim of the storm was 26-year-old Mexican man who was killed as he tried to cross a river.
Ports for small vessels in the area have been closed and emergency services in Oaxaca said they evacuated residents from some areas as a precaution, including the immediate vicinity of the refinery.
A tropical storm warning is in effect from Salina Cruz in Oaxaca to Pijijiapan in Chiapas state.
Between 10 to 20cm of rain is expected over eastern Oaxaca through western Chiapas, along with a storm surge of 1 to 1.5m above normal tide levels, the NHC said.
The storm had made landfall in the state of Chiapas, a rural region with archeological sites near the neighboring state of Oaxaca. Hundreds of people were being evacuated from affected areas in Chiapas, state civil protection officials said.
In the state of Guerrero, heavy rains flooded some streets of the resort city of Acapulco, with water levels reaching 52cm and sweeping away at least three cars, an AFP correspondent said.
Oaxaca authorities had urged residents to stay home, while the ports of Salina Cruz, Huatulco, Puerto Angel and Puerto Escondido were shut down. Some 200 families were taken to shelters, officials said.
Barbara grew into a category one hurricane - the lowest on the five-level Saffir-Simpson scale - before making landfall west of the Chiapas town of Tonala, the US hurricane center said.
"These rains could cause life-threatening flash floods and mudslides," it warned.
In March 2012, two girls died and 25,000 homes were affected when Hurricane Carlotta tore across Oaxaca.