The remnants of Tropical Storm Matthew dumped torrential rains on southern Mexico and much of Central America on Sunday, killing at least four people as it let loose floods and mudslides across the water-logged region.
In El Salvador, a 32-year-old man was killed when he was swept away by a swollen river, and another person was missing, authorities said.
In Mexico's southern Chiapas state, three Tzeltal Indians, two of them children, perished when their house collapsed during a heavy rainstorm.
"It happened late Sunday, when flood waters swept away a house and its three occupants," said Chilon town official Julian Hernandez.
Chiapas Civil Protection director Luis Manuel Garcia said Matthew caused heavy damage across the state.
"There are mudslides in eight municipalities... The worst damage is in Yajalon town, where 215 homes have been affected and around 1,000 families have moved to shelters," he said.
Five states in southern and eastern Mexico were under storm alerts due to the heavy rains, including Veracruz, still suffering from Hurricane Karl earlier this month.
At 1500 GMT the center of the remnant low pressure area was moving westward over far southern Mexico and "could become nearly stationary by tonight," the Miami-based National Hurricane Center said.
Destructive winds were no longer the concern; authorities were on red alert for more flooding and mudslides in a mountainous region that is in the midst of one of the most intense rainy seasons in the past 60 years.
In a sign of increasing danger for Mexico and Guatemala, the NHC raised its forecast for rainfall as the weather system slowed its forward crawl over the region.
The system "is expected to produce total rain accumulations of 25-50 centimeters (10 to 20 inches) from far southern Mexico into northern portions of Central America with isolated maximum amounts of 76 centimeters (30 inches) possible," the Miami-based NHC warned.
"These rains could produce life-threatening flash floods and mudslides," it stressed.
Thousands in rural Central America live close to rivers likely to burst their banks, because they depend on them for water and farming.
Karl left 14 people dead in Veracruz earlier this month, and an estimated 400,000 people homeless.
Mexico has said it is being lashed by the wettest rainy season on record.
Flooding and landslides have killed more than 300 people in Central America, left tens of thousands homeless and caused billions of dollars in damage in recent months, officials said.