Hurricane Gustav strengthens slightly

NEW YORK (Reuters) - Hurricane Gustav strengthened slightly early Tuesday in the central Caribbean as it churned toward south-western Haiti, the U.S. National Hurricane Centre said in its latest report.

Gustav was located about 75 miles south-southeast of Port-au-Prince, Haiti, moving northwest at about 9 miles per hour, with maximum sustained winds up slightly at 90 mph.

The storm was expected to move over south-western Haiti later today and then head just south of Cuba later this week.

Weather models show the storm either heading in a westerly direction toward Mexico's Yucatan Peninsula or steering northwest and moving into the central Gulf of Mexico by early Sunday, a track that could cause some disruption to offshore Gulf oil and gas production.

A hurricane watch was issued for Jamaica and parts of Cuba, meaning high winds and rain are possible within that area, generally within 36 hours.

Gustav is a category one hurricane, the lowest rating on the Saffir-Simpson scale, but could strengthen to a category two storm with winds above 95 mph before making landfall in Haiti later today.

The NHC was also monitoring a large area of low pressure about 200 miles east-northeast of the northern Leeward Islands.

Conditions appear favourable for slow development of this system over the next couple of days, but the projected track showed it steering in a north or north-westerly direction, which could take it away from the U.S. East Coast.

Energy traders watch for storms that could enter the Gulf of Mexico and threaten U.S. oil and gas production facilities.

Commodities traders also watch storms that could hit agriculture crops like cotton in Texas and citrus in Florida.

The next report will be issued by the NHC at 11 a.m. EDT (4 p.m. British time.)

(Reporting by Joe Silha, editing by John Picinich)