By Ivan Castro
MANAGUA (Reuters) - Tropical Storm Ida strengthened off the coast of Nicaragua on Wednesday as heavy rains forced a Caribbean island to evacuate and the Central American nation, fearing devastating mudslides, was put on hurricane watch.
Ida, the ninth named storm of the Atlantic hurricane season, dumped rain on northern Nicaragua and around 300 people fled the popular tourist spot Corn Island to wait out the storm in government-run shelters.
Dark clouds and rains menaced Managua, Nicaragua's capital, and the U.S. National Hurricane Centre said a hurricane watch was in effect for the eastern coast up to the border with Honduras.
"A hurricane watch means that hurricane conditions are possible within the watch area, generally within 36 hours," the hurricane centre said.
The storm had maximum sustained winds of nearly 65 miles per hour (100 km/hr) and could dump up to 25 inches (64 cms) of rain on Nicaragua and eastern Honduras.
"These rains could produce life-threatening flash floods and mudslides," the NHC's forecast said.
The head of Nicaragua's emergency services network, Ramon Arnesto, said up to 15,000 people along the Caribbean coast could be affected by the storm.
Coffee producers, just starting a new harvest, are watching weather developments closely, but say their crops in the mountainous regions near the Honduran border are far from strong coastal winds. Landslides could wash out roads to coffee farms or heavy rain could knock ripening cherries off trees, said Luis Osorio, technical director at the national coffee council.
Tropical storm warnings were in effect for all of eastern Nicaragua and for some nearby islands belonging to Colombia.
The NHC's longer-term forecast showed Ida passing over Central America and regaining tropical storm strength by Monday off Mexico's Yucatan peninsula. That could take it into the oil and gas-rich Gulf of Mexico.
Forecasters said the storm's proximity to land made predicting its long-term path and intensity more difficult than usual.
In Mexico, heavy rains in the Gulf of Mexico -- unrelated to Ida -- have already killed three people in floods and closed two of the country's main crude exporting ports. (Additional reporting by Robert Campbell in Mexico City; editing by Chris Wilson)