The Weekly Fill-Up | July 20-24

July 20, 2026

For much of the year, conversations about fuel prices have centered on crude oil. This week, however, one of the most important numbers for diesel users may not be the price of crude at all. It is the amount of finished diesel actually available.

Global refining conditions have tightened considerably, creating an unusual market where crude oil supplies have shown signs of recovery while the fuels produced from that crude remain under pressure. For Sioux Valley Coop patrons, this distinction is becoming increasingly important as we move through summer and begin looking ahead toward fall agricultural demand.

Recent U.S. data offers a good example of the situation. Diesel and other distillate inventories increased significantly during the latest reporting period, providing some much-needed rebuilding of domestic supply. Even after that increase, however, U.S. diesel stocks remained below both levels seen earlier this year and the five-year seasonal average.

That means the market has gained some breathing room, but the overall supply cushion remains relatively thin.

The challenge extends well beyond the United States. Refining disruptions in several parts of the world have reduced the amount of gasoline, diesel, jet fuel, and other finished petroleum products entering the global market. Conflict-related disruptions have affected refinery operations in the Middle East and Russia, while refining activity in other major markets has also faced constraints.

This matters because having crude oil available does not automatically mean there is enough diesel available. Crude must first be transported and processed through refineries before it becomes usable fuel. When global refining capacity is constrained, the value of finished products can remain elevated even if crude oil prices stabilize or decline.

For agricultural diesel users in eastern South Dakota, this creates a market worth watching carefully as summer progresses.

Local fuel supply remains dependable, but the broader diesel market has less flexibility to absorb unexpected disruptions. A refinery outage, additional international supply disruption, or sudden increase in demand could have a greater impact when inventories are already relatively tight.

There is another factor adding uncertainty this week: renewed tension involving major Middle Eastern shipping routes. Oil markets moved higher late last week as conflict between the United States and Iran intensified and concerns grew about additional disruptions to shipping. These routes are important not only for crude oil but also for refined petroleum products moving between major producing and consuming regions.

At the same time, developments in China could become an important wildcard for global diesel supply. Chinese refinery activity and crude imports have fallen significantly amid recent market disruptions. If Chinese refiners increase production and exports of diesel and other refined products, that additional supply could help ease some pressure on international markets. If exports remain limited, however, competition for available diesel could stay elevated.

Here in South Dakota, the timing deserves attention because agriculture is moving toward another change in fuel demand.

Summer operations such as haying, spraying, livestock work, transportation, and construction continue to create steady diesel consumption. Before long, preparations for fall fieldwork and harvest will begin adding another layer of demand. The market conditions we see in July can therefore influence the supply and pricing environment producers encounter heading into late summer.

Propane is currently providing a more stable picture. Summer remains an important inventory-building period, when lower heating demand allows suppliers to position gallons ahead of fall and winter. For propane customers, the current season is less about immediate demand pressure and more about how effectively inventories build before colder weather and agricultural demand return.

The biggest takeaway for the week of July 20 is that fuel markets should not be judged by crude oil prices alone. The ability of the global refining system to turn crude into diesel has become one of the most important factors influencing today’s market.

For Sioux Valley Coop patrons, dependable local supply remains the priority. As we move closer to late-summer and harvest demand, keeping an eye on fuel needs and planning purchases based on operational requirements rather than crude oil headlines alone can provide a clearer picture of what is actually happening in the diesel market.

Sources

U.S. Energy Information Administration (EIA), Weekly Petroleum Status Report and Gasoline and Diesel Fuel Update. EIA data showed U.S. diesel/distillate stocks recently increased but remained below the five-year seasonal average.
U.S. Energy Information Administration (EIA), Short-Term Energy Outlook, for current petroleum-product market and pricing outlooks.
Reuters, July 20, 2026, reporting on pressure across the global refining system and tight inventories of finished fuels despite the partial recovery in crude supply.
Reuters, July 17–20, 2026, reporting on renewed U.S.-Iran tensions, oil-shipping risks, and China’s changing crude imports, refinery activity, and potential refined-product exports.