Except for the Chandelier Islands, LA the oil has remained off shore since it first started to gush on April 20.. However, this week a strong high pressure ridge anchored in the southeast will likely pull some of the oil that has been off shore, closer to Louisiana. Some barrier islands like Point Au Fer Island in southern Louisiana will be the first to see the oil on its shores. The marshes and wildlife will be the hardest hit as the oil continues to pull West towards Atchafalaya Bay. The map above shows how the natural currents in the gulf shaped the oil slick.
The oil sheen is also steered by the constantly changing winds in the gulf. This week the winds shift to the southeast and strenghten over time. Containment booms will be difficult to control with dispersant's and sand bags as the first line of defense.
It's still too early to tell if the oil will hurt the delicate ecosystem the marshes and wetlands provide in the Gulf of Mexico. The long term impacts could be continued loss of wetland habitat for the next several years. Since the wetlands act as a buffer for storm surge flooding the city of New Orleans could face another difficult hurricane season like it did in 2005 with Hurricane Katrina.