The remnants of Hurricane Dean have brought torrential rain to Mexico, raising fears of floods and mudslides.
More than 20,000 people have fled their homes in Veracruz state
Up to 51cm (20in) of rain were expected in parts of southern and central Mexico as Dean hit the country for the second time this week.
Winds of 35mph (55km/h) were also expected, but forecasters say the storm should dissipate later on Thursday.
Dean was downgraded from a Category Two hurricane to a tropical depression on Wednesday evening.
The hurricane first crossed Mexico's Yucatan Peninsula on Tuesday as a maximum Category Five storm, toppling trees, wrecking homes, and causing flooding.
It also damaged houses and flooded streets in neighbouring Belize.
Dean has claimed at least 18 lives since it began its path through the Caribbean last week.
The first Mexican fatality was reported on Wednesday when a man in Veracruz state was killed by an overhead power cable as he tried to repair the roof of his house.
The US National Hurricane Center (NHC) forecast a total rainfall of 5-10in over parts of southern and central Mexico, with a maximum of up to 20in in the central mountains.
"These rains could cause life-threatening flash floods and mudslides," said a statement from the centre.
NHC spokesman Jamie Rhome warned residents not to underestimate Dean.
"We often see that when a storm weakens, people let down their guard completely. You shouldn't do that," he told the Associated Press news agency.
The Veracruz state government said residents of poor mountain villages were particularly at risk.
"It's raining and it's going to keep raining intensely in the coming days," Veracruz Governor Fidel Herrera said.
More than 20,000 people were also evacuated from low-lying coastal areas of the state as local rivers swelled.
Oil production to resume
Meanwhile, the Mexican state oil company, Petroleos Mexicanos (Pemex), said technicians were set to return to its offshore oil platforms and would begin to restore output on Friday.
Hundreds of homes were destroyed in and around the town of Majahual
Pemex evacuated all 18,000 employees from its installations in the Gulf of Mexico before the hurricane struck, causing a drop in production of 2.65m barrels a day.
Major Mexican tourist resorts were not directly hit, but indigenous Mayan villages were exposed to the hurricane's full force when it struck the Yucatan Peninsula south of Cancun.
Hundreds of homes were destroyed in and around the town of Majahual.
Before it hit Mexico, Dean killed nine people in Haiti, four in Jamaica, two in the Dominican Republic and two in Martinique.
It also forced Jamaican authorities to delay until 3 September a general election that had been scheduled for next week.