September crude oil grinded lower during the early morning hours, weighed down by a weak outside market tone, with growing concerns surrounding the US debt ceiling impasse, fresh sovereign debt concerns in Spain and fears of slowing economic growth. Meanwhile, EIA data yesterday revised their May oil demand estimates lower, noting the increase in gasoline prices toward $4.00 as a factor weighing on consumption. This decline in May oil demand marks the second consecutive month over month decline and is seen as a negative. On the weather front, Gulf of Mexico interests have prepared for Tropical Storm Don, with the estimates yesterday indicated that about 7.0% of the regions production was shut down, about 95,000 barrels per day.