West Coast or Petroleum Administration for Defense District (PADD) 5 transportation fuels markets are tightly balanced, relatively isolated, and, in some cases, have unique product specifications, which often results in significant and persistent increases in prices in the wake of supply disruptions. On September 30, the U.S. Energy Information Administration (EIA) released the PADD 5 Transportation Fuels Markets study, which examines transportation fuels (motor gasoline, distillate fuel, and jet fuel) supply, demand, and distribution at both the PADD level and for specific areas within PADD 5.

PADD 5 covers a large and diverse geography, and supply/demand balances and distribution patterns vary within the region. The study identified six distinct regional markets within PADD 5: Southern California and Southern Nevada; Northern California and Northern Nevada; Pacific Northwest, which includes Washington and Oregon; Arizona; Hawaii; and Alaska. These six regional markets vary significantly in demand; how transportation fuels are supplied, especially the share of supply provided by in-region refineries; and product distribution patterns.