The national retail average price for diesel monitored by the American Automobile Association has risen to $6.3956 per gallon, marking the highest value recorded in this series and approaching the $6.40 threshold for the first time. The previous day was $6.3103, a week ago it was $5.9773, a month ago it was $5.4454, and a year ago it was $3.7075.

The Energy Information Administration's weekly average for highway diesel reached $6.285 during the week of September 14, up $0.318 from the previous week’s $5.967, and up $2.546 year-on-year, approximately 68%. That week, California saw $8.039, the West Coast $7.250, and the Gulf Coast reached $6.027, with all top ten regions above $6. GasBuddy reported earlier that the national average had first crossed $6.

The driving force comes from refined oil rather than just crude oil. The war between the U.S. and Israel against Iran has disrupted transportation in the Strait of Hormuz, which carried about one-fifth of the world's crude oil before the conflict; strikes on Russian refineries by Ukraine continue to deplete diesel supplies. U.S. diesel inventories are about 13% lower than the five-year average, which was around 106.3 million barrels. The U.S. diesel crack spread once surged to a record $112.17 per barrel. Brent settled at $107.63 that day, while WTI settled at $102.48.

The previous high from 2022 has now been surpassed. The AAA's previous high of about $5.8159 occurred on June 14, 2022, corresponding to the shortage of distillate fuel following the outbreak of the Russia-Ukraine war. This time, the price rose from about $3.76 before the war to around $6.27, an increase of over 66%; diesel has risen from just over $3 to above $6 in five years. The national average price for regular gasoline during the same period was about $4.44, with the price gap between diesel and gasoline widening again.

The real sector is already reporting cash flow disruptions. The energy director of Kansas fuel supplier Oasis Energy stated that diesel prices have more than doubled in five months, impacting cash flow. GasBuddy analysts pointed out that costs for trucking, distribution, packaging, and procurement are all rising, and freight surcharges will reopen a round of price increases along the supply chain. Agricultural machinery, construction equipment, and cold chain logistics also burn diesel, and price increases will first impact food and building materials, rather than just private car owners.

The market mechanism is a refined oil shortage driven by war, not seasonal travel. Buyers are carriers, farms, and contractors that must operate vehicles, with low price elasticity, and can only pass fuel surcharges onto shippers; sellers are refineries that can still operate at full capacity, profiting from record crack spreads. Beneficiaries are refiners' margins and traders holding distillate inventories; those under pressure include trucking, retail logistics, food distribution, and the governing cycle that has made "lower energy prices" a campaign promise. Capital flows are towards crude oil and diesel crack longs, and refinery stocks, while shorts are shippers and consumer stocks hedging transportation costs.

In supplementary data, the EIA's short-term outlook previously projected the average annual price for highway diesel in 2026 at $5.07, and $4.40 the following year, but retail prices have already surpassed this trajectory. California pump prices are nearing or exceeding $8, becoming the highest anchor point in the nation; the national average jumped from $5.599 at the end of August to $6.285 in just two weeks, and then pushed to around $6.40 by AAA's daily readings.

Source: Public Information