Oil prices have been under attack in the last few weeks, perhaps a remarkable turn around given what is considered normal for this time of year. At last look, oil prices began this week by shedding nearly $2/bbl, bringing them down to $89/bbl, something that is highly unusual this time of year, but goes to show how rising domestic supply and availability may be keeping a lid on oil prices.

The good news is that lower oil prices will be a leading contributor to lower pump prices, which as of this morning stand nearly 40c/gal lower than they did a year ago. Hawaii is the lone state where gasoline prices remain above an average of $4/gallon, and due to unique issues there, will likely remain above $4/gallon.

Across the rest of the United States, prices will likely continue to slip this week. We could start to see a few $2.99s popping up in the week ahead in the south, with some $2.99's spread around South Carolina, Texas, Tennessee, and Oklahoma.

OPIS and GasBuddy estimate that the per diem aggregate fuel cost for American motorists is at least $170-million below last year. The distance may even be greater, since GasBuddy calculates that the gap between the best motor fuel price offers and the average numbers has continued to be much wider than it was in 2012.

And the situation continues to look bright as refineries return from maintenance and boost production ahead of the all important start to the summer driving season: Memorial Day.