Ida's threat ebbs but Gulf energy output disrupted

By Kelly Dugan

MOBILE, Alabama (Reuters) - A weakened Tropical Storm Ida drenched the U.S. Gulf Coast and oil installations on Monday, shutting down nearly 30 percent of Gulf energy production.

Ida was expected to strike the coast near Mobile, Alabama, early on Tuesday. At one time a Category 2 hurricane, Ida's threat eased as winds dropped to 70 miles per hour (112 km per hour). They were expected to decrease further as the storm approached landfall.

A U.S. Coast Guard helicopter plucked two workers from a storm-damaged oil rig about 80 miles (130 km) south of New Orleans. Ida is blamed for 124 flood and mudslide deaths in El Salvador.

The Coast Guard closed the Port of Mobile, halting traffic on Mobile Bay, and authorities closed schools and government offices in coastal counties in Alabama and Florida, telling residents of flood-prone areas and mobile homes to evacuate.

Ida, which was downgraded to a tropical storm earlier on Monday, posed the first real storm threat of the 2009 Atlantic hurricane season to Gulf of Mexico oil and natural gas production, and forced some companies to shut down off-shore platforms and evacuate personnel.

The U.S. Minerals Management Service said that Ida had shut down 29.6 percent of Gulf oil production and 27.5 percent of gas output.

Energy markets have been hypersensitive to Gulf cyclones since the devastating 2004 and 2005 seasons, when storms like Katrina disrupted U.S. output and sent pump prices soaring.

Although Ida's winds were still near hurricane force, most offshore oil rigs in the Gulf won't see winds over 50 mph (80 kph), said Jim Rouiller, senior energy meteorologist at private forecaster Planalytics Inc.