By Herbert Hernandez
GUATEMALA CITY (Reuters) - Guatemalans prepared on Saturday for the arrival of Tropical Storm Agatha, the first named storm of the 2010 Pacific hurricane season, which was expected to bring heavy flooding to some areas.
Emergency workers reported rivers were already swollen by heavy rain and warned flooding could be worse than usual due to ash from the erupting Pacaya volcano south of the capital that has blocked drainage systems.
The U.S. National Hurricane Centre said Agatha formed on Saturday morning and had maximum sustained winds of 40 miles per hour (65 kph). Agatha was located 170 miles (275 km) west-southwest of the port of San Jose in Guatemala and was expected to make landfall in Guatemala on Sunday.
The Miami-based hurricane centre said the storm would dump up to 20 inches (50 cm) of rain over southeastern Mexico, Guatemala and El Salvador which could trigger flash floods and mudslides.
"We think that given the expected development of the storm we will declare a red alert for the whole country in a few hours," said Yohana Miner, an emergency services spokeswoman.
Guatemalan meteorologists warned the rains could persist through Tuesday.
Tropical storm warnings were posted for the Pacific coast from Boca de Pijijiapan in southern Mexico to the El Salvador-Honduras border.
Some 2,000 people have already been evacuated from their homes due to the eruption of Pacaya, located 25 miles (40 km) south of Guatemala City. At least one death has been blamed on the eruption and the country's main international airport has been shut.
The volcano, which erupted on Thursday, was still active but the intensity of its activity appeared to be diminishing, a civil defence official said.
Pacaya has been active since the 1960s but had not ejected rocks and ash since 1998.
The volcano is close to some of Guatemala's most prized coffee plantations. The national coffee association, Anacafe, had no immediate reports of serious damage to crops.
Coffee workers said on Friday rain from the storm was helping to clean ash off trees and were optimistic crop damage would be minimal.
Nancy Mendez, a spokeswoman for Anacafe, said poor communications were hampering the agency's efforts to collect information on the state of the crop.
(Additional reporting and writing by Robert Campbell; Editing by Eric Walsh and Alan Elsner)
