Hurricane Omar revs up off Puerto Rico

MIAMI (Reuters) - Hurricane Omar strengthened slightly on Wednesday as it bore down on Puerto Rico and the small islands of the northeastern Caribbean, the U.S. National Hurricane Center said.

Omar, which grew quickly from a tropical storm on Tuesday, had top sustained winds of 80 mph (130 kph) as it swirled about 265 miles (425 km) south-southwest of Puerto Rico, the Miami-based hurricane center said.

Additional strengthening was forecast over the next 24 hours, and Omar could become a Category 2 hurricane on the Saffir-Simpson intensity scale, with winds of at least 96 mph (155 kph), by the time it reaches the northern islands, forecasters said.

In Venezuela, the storm stopped tankers from loading crude oil at refinery facilities and knocked out power at the OPEC nation's 200,000 barrel-per-day Puerto La Cruz refinery, officials said.

While a tropical storm, the 15th of the Atlantic hurricane season, Omar had formed north of the Netherlands Antilles island of Curacao and revved up over warm Caribbean waters.

Hurricane warnings or alerts were posted for Puerto Rico, the U.S. and British Virgin Islands and other islands including Antigua and Barbuda, Anguilla, St. Kitts and Nevis, Saba, St. Eustatius, St. Martin and St. Barthelemy.

On Curacao, a small tourist island north of Venezuela, trees and lampposts were knocked down on Tuesday and power was knocked out in some areas. Stores in the capital closed due to flooding. Residents reported seeing waves up to 16 feet (5 metres) high.

There were no reports of deaths or injuries and local meteorologists said the weather was set to improve.

Omar was moving on a track that would take it over the northern Leeward Islands on Wednesday night and early Thursday. Forecasters said it could produce up to 20 inches (51 cm) of rain.

"These rains could produce life-threatening flash floods and mudslides," the hurricane center said.

STORM OFF HONDURAS

Another weather disturbance, a tropical depression off Honduras, was expected to strengthen into Tropical Storm Paloma, the 16th of the season, later on Wednesday.

At 8 a.m. EDT (1200 GMT), the depression was 95 miles (150 km) east of Limon, Honduras, and expected to be just off the coast of northern Honduras during the next day or two.

Forecasters said it did not appear to present a threat to the U.S. mainland or Gulf of Mexico oil fields.

The 2008 hurricane season, which officially ends on Nov. 30, has been active so far.

An average season spawns 10 storms, of which six grow into hurricanes. This year, Hurricane Gustav slammed ashore near New Orleans, the city devastated by Hurricane Katrina in 2005, and Hurricane Ike hit Houston. Both threatened oil rigs off the U.S. Gulf Coast, which supply a quarter of U.S. domestic oil.

In Haiti, more than 800 people were killed after the impoverished Caribbean nation was swamped by Fay, Gustav, Hanna and Ike. Cuba suffered $5 billion in damage after being raked by Gustav and Ike.