Gulf of Mexico crudes strengthened against the benchmark West Texas Intermediate as companies including Royal Dutch Shell Plc and BP Plc began moving workers off Gulf platforms because of Tropical Storm Isaac.
The storm was expected to make landfall in Haiti late today and approach the Florida Keys on Aug. 26 before heading into the eastern Gulf of Mexico, according to a National Hurricane Center advisory at 5 p.m. New York time today.
The Gulf region is home to 23 percent of U.S. oil production, 7 percent of natural-gas output and 44 percent of refining capacity, according to the U.S. Energy Department.
Mars Blend, Poseidon, Southern Green Canyon and Thunder Horse all added at least $1 to their premiums. Mars Blend’s premium gained $1.05 to $14.40 a barrel more than WTI at 4:18 p.m. New York time, according to data compiled by Bloomberg. Poseidon gained $1.15 to $14.60. Southern Green’s premium rose $1 to $14. Thunder Horse strengthened $1 to a premium of $16.50.
Light Louisiana Sweet oil weakened by $1.05 to a premium of $18.65 a barrel against WTI in Cushing, Oklahoma. Heavy Louisiana Sweet oil strengthened 50 cents to a premium of $19.50.
Bakken oil’s discount to WTI grew 50 cents to $3 a barrel. Western Canada Select’s discount narrowed 50 cents to $15.50 a barrel, and WTI in Midland, Texas, in the middle of the Permian basin, weakened 50 cents to a discount of $1.75 a barrel.