EL Salvador Interior Minister Mario Duran said Monday some 7000 people were scattered across 154 shelters. He said a quarter of the rain that the country normally receives in a year fell in 70 hours.

That set off landslides and flooding, especially in the western part of the country. A day earlier officials had said at least 900 homes had been damaged.

President Nayib Bukele visited one of the most affected communities on the outskirts of San Salvador. Some 50 families lost their homes and Bukele said the government would give them money to rebuild.

One whose home was damaged was Maria Torres. "We've never experienced this," she said. "The rain was so strong and suddenly the water entered the homes and we just saw how they fell."

The Legislative Assembly approved the government's use of a $US389 million ($A583 million) loan from the International Monetary Fund to deal with the pandemic and the storm's impact.

El Salvador reports more than 2500 infections and 46 deaths.

In Guatemala, a nine-year-old boy was swept away by a river and drowned and another person was killed when a home collapsed, said David de Leon, spokesman for the national disaster agency.

Amanda pounded El Salvador with rain for days before moving ashore as a tropical storm on Sunday and pushing across Guatemala.

It quickly dissipated, but the US National Hurricane Center said Monday afternoon its remnants had formed into a tropical depression in the Bay of Campeche off Mexico's gulf coast and was expected to move through the Gulf of Mexico in coming days.

Mexico issued a tropical storm warning from Campeche west to the port of Veracruz, expecting the depression to become a tropical storm Monday night or Tuesday.

It had sustained winds of 45km/h and was expected to move slowly just off the Mexican coast for the next couple days.

The storm is expected to dump 25 to 38 centimetres of rain over the Mexican state of Tabasco and Veracruz with up to 50cm in some isolated areas.

Australian Associated Press