Brent Crude Tops $104 as Hormuz Tanker Attacks and Hurricane Isaias Trigger Dual Supply Shock

Oil prices surged more than 4% on Thursday as two simultaneous supply disruptions rattled energy markets: escalating Iranian attacks on tankers in the Strait of Hormuz and Hurricane Isaias knocking out more than 60% of U.S. Gulf of Mexico oil production. Brent crude settled at $104.28 per barrel, up $4.08 or 4.07%, while November WTI crude closed at $91.49, a gain of $3.21 or 3.64%. RBOB gasoline futures jumped 4.52% and diesel futures added roughly 50 cents from Tuesday morning, with November diesel settling at $4.8829 per gallon.

U.S. Central Command held a virtual briefing with international shipping partners on Thursday, with Admiral Brad Cooper, CENTCOM commander, acknowledging sacrifices made by civilian crews because of what he called unwarranted Iranian attacks. CENTCOM said U.S. forces have supported the transit of more than 1.25 billion barrels of crude from Gulf partners through the strait in recent months, with daily flows on Wednesday reaching 20 million barrels and touching 22 million barrels on a single day, levels described as matching prewar norms. Iran has not exported any barrels, CENTCOM said, citing an American blockade on Iranian ports. Late Thursday, Iranian state-linked media reported powerful explosions in the southern strait after tankers allegedly struck mines, adding a fresh layer of risk.

Hurricane Isaias, the first hurricane of the 2026 Atlantic season, rapidly intensified as it approached the northern Gulf Coast, expected to make landfall late Friday or early Saturday with damaging winds, life-threatening storm surge and flooding. Operators shut in approximately 1.28 million barrels per day, or nearly 63% of Gulf oil output, and 1.1 billion cubic feet per day of natural gas production, evacuating personnel from 121 of the Gulf's 371 manned platforms. Jefferies warned of a potential fuel supply event, with analysts noting that nearly 500,000 barrels per day of refining capacity sits in the storm's projected path. National gasoline prices averaged $4.36 per gallon as of Wednesday, while diesel, which set an all-time record in September, stood at $6.28 per gallon.

The twin shocks pulled stocks lower. The S&P 500 fell 0.26%, the Dow declined 0.31%, and the Nasdaq 100 dropped more than 1.5%, with chip stocks adding additional pressure alongside reports that OpenAI's revenue fell $20 billion short of earlier projections.