Nov. 5 (Bloomberg) -- Hurricane Ida weakened to a tropical storm after washing ashore today in eastern Nicaragua, where it is forecast to dump enough rain to unleash life-threatening floods and mudslides, the U.S. National Hurricane Center said.

Rain from Ida was drenching much of northern and eastern Nicaragua and may total as much as 20 inches (64 centimeters) in the country and Honduras, the U.S. agency said. The storm ripped at roofs and downed trees on Big Corn Island, a tourist resort off Nicaragua’s coast.

“We’re lucky our hotel is still standing,” Juana Salinas, manager of Hotel Morgan on Big Corn Island, said in a telephone interview.

Nicaraguan President Daniel Ortega decreed a national alert as Ida approached, General Mario Perezcassar, head of the county’s civil defense body, said in a phone interview. The rain led authorities to evacuate more than 2,200 people from islands off the coast and from shanties near the port city of Bluefields, he said.

Neighboring Costa Rica also declared a state of emergency as flooding destroyed several homes along its northern Caribbean coast, the country’s national emergency agency said today in an e-mailed statement.

Ida was centered about 50 miles (85 kilometers) south- southwest of Puerto Cabezas, Nicaragua, as of about 3 p.m. local time, the Miami-based center said in a statement. The system is moving north-northwest at about 3 mph and is expected to speed up and turn to the north tonight or tomorrow.

Winds Slow

The storm’s maximum sustained winds dropped to near 60 mph from 75 mph earlier today, and Ida is forecast to weaken into a depression tomorrow.

A tropical-storm warning is in effect for Nicaragua’s eastern coast from Bluefields north to the Honduras border, meaning sustained winds as strong as 73 mph are expected within a day. A tropical-storm watch was issued for the northeastern coast of Honduras from Limon to the east to the border with Nicaragua.

The storm is forecast to pass over Honduras as a depression and then re-intensify into a tropical storm as it moves back into the Caribbean this weekend. It should pass just east of Mexico’s Yucatan Peninsula on the morning of Nov. 9 and then north into the Gulf of Mexico, home to about a quarter of U.S. oil production, according to a five-day track prediction.

Crude oil for December delivery fell 78 cents to settle at $79.62 a barrel on the New York Mercantile Exchange. Futures have gained 79 percent this year.

To contact the reporter on this story: Chris Dolmetsch in New York at cdolmetsch@bloomberg.net

Last Updated: November 5, 2009 16:15 EST