GUATEMALA CITY (AP) - Tropical Storm Agatha, the first of the season, formed in the East Pacific on Saturday, generating heavy rains in Guatemala and killing four people when a dislodged boulder crushed their house, authorities said.
The rains also threatened to turn black ash dumped by a huge volcanic eruption into cement-like mud.
Agatha was centered about 170 miles (275 kilometers) southwest of Puerto de San Jose, Guatemala, and moving toward the northeast at 5 mph (8 kph), said the U.S. National Hurricane Center in Miami.
It had maximum sustained winds of 40 mph (64 kph) and some strengthening was expected.
The storm was expected to dump from 10 to 20 inches (25 to 50 centimeters) of rain and as much as 30 inches (75 centimeters) in isolated areas of Guatemala, threatening dangerous floods and mudslides.
A tropical storm warning was in effect Sunday for a stretch of coastline from El Salvador to far-southern Mexico.
Guatemalan disaster relief spokesman David Leon said officials worry that the rains could exacerbate damage in the country, where explosions from the Pacaya volcano have destroyed 800 homes this week.
Leon said two children and two adults were killed Saturday when rains generated by Agatha dislodged a boulder that crushed a house they were in.
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