El Salvador's President Nayib Bukele declared a state of emergency for 15 days to cope with the effects of the storm, which lost strength later in the day as it moved into Guatemala.
The fatalities were all recorded in El Salvador, senior cabinet official Carolina Recinos said, adding that one person is reported missing.
In the capital, San Salvador, 50 homes were damaged by rain and powerful winds, while 23 vehicles were swallowed by a sinkhole, Mayor Ernesto Muyshondt said.
"We are experiencing an unprecedented situation: one top-level emergency on top of another serious one," he said, referring to the COVID-19 pandemic in place before the rain hit.
In some flooded areas, soldiers worked alongside emergency personnel to rescue people.
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