UPDATE 1-Tropical storm Ida could trigger Nicaragua mudslides

(Rewrites with upgrade to tropical storm)

MEXICO CITY, Nov 4 (Reuters) - Tropical Storm Ida strengthened off the Caribbean coast of Nicaragua on Wednesday, threatening the Central American nation with torrential rains that could trigger devastating mudslides.

Ida, the ninth named storm of the Atlantic hurricane season, was expected to make landfall in eastern Nicaragua overnight.

The storm had maximum sustained winds of nearly 60 miles per hour (95 km/hr) and could dump up to 25 inches (64 centimeters) of rain on Nicaragua and neighboring Honduras, the U.S. National Hurricane Center, or NHC, said.

"These rains could produce life-threatening flash floods and mudslides," the NHC's forecast said.

Ida could strengthen further before making landfall, the NHC said.

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 called for Ida to pass over Central America and regain tropical storm strength by Monday off Mexico's Yucatan peninsula, which could take it into the oil- and gas-rich Gulf of Mexico.

However, forecasters said the proximity of the storm to land made longer-term estimates of Ida's path and intensity more difficult than usual. (Reporting by Robert Campbell; editing by Todd Eastham)