Brent tops $102 as a quarter of Gulf oil output shuts in and Hormuz attacks pick up

Oil is rising this morning for two reasons at once, and they come from opposite ends of the map. A hurricane is bearing down on the US Gulf Coast, taking offshore production offline, while the shipping lanes around the Persian Gulf are becoming more dangerous again.

December Brent crude futures traded as high as about $104 a barrel in European hours, up from a $100.20 settlement on Wednesday. Earlier quotes put Brent at $102.28 to $102.79, gains of 2.3% to 2.6%. US crude followed: November West Texas Intermediate rose to about $91.30, and the December WTI contract was near $89.50.

Isaias is now a hurricane

Isaias strengthened into the first hurricane of the 2026 Atlantic season late Wednesday. The National Hurricane Center forecast it to make landfall on the northern Gulf Coast early Saturday, bringing storm surge, heavy rain and possible tornadoes, with a probable path toward the Florida Panhandle.

Producers did not wait. As of Wednesday, offshore operators had shut in about 25.08% of Gulf of Mexico oil production and 16.37% of its natural gas output, according to the Marine Minerals Administration, the regulator that combined the former BOEM and BSEE. Eight of the 371 staffed production platforms had been evacuated, along with two drilling rigs. Trade press estimates put the lost output at roughly half a million barrels a day.

Shell said it was evacuating personnel and shutting in production at its Mars, Olympus, Ursa, Vito and Appomattox assets. Chevron said it had begun shut-in procedures at four of its Gulf facilities while the other five continued normal operations. Harbour Energy also evacuated its Gulf assets.

Shut-ins are a safety step, not damage. The number that matters for oil prices is how quickly platforms come back after inspection once the storm has passed.

The regulator notes that undamaged facilities are usually brought back online quickly after post-storm checks. If the storm stays on the eastern edge of the oil patch, the disruption could be short; a track farther west, or damage to platforms or pipelines, would make it longer.

Hormuz: the bigger, slower problem

The storm is the near-term story; the Persian Gulf is the structural one. Attacks on merchant ships in the Strait of Hormuz picked up to their fastest pace since the Iran war began on February 28, and traffic through the waterway dropped to its lowest level in more than two months, The Daily Energy reported, citing tanker-tracking data. The Wall Street Journal also cited another tanker strike in the Persian Gulf and escalating Houthi attacks in Saudi Arabia.

That reverses the mood from earlier this week. Brent briefly traded below $100 when tanker trackers said crude flows through Hormuz were approaching pre-war levels, and prices dipped again on Wednesday after International Energy Agency members agreed to speed up emergency stock releases. Thursday's move wiped out that dip.

Diplomacy offered little relief overnight. US stock futures slipped after President Donald Trump said a deal with Iran was "not really something" he wants, according to Seeking Alpha.

Why it matters beyond the oil patch

Oil near $100 has become one of the main inputs into the inflation debate at the Federal Reserve. The minutes of the Fed's September meeting showed some officials backed the rate increase specifically to keep energy shocks from spreading into broader prices. Higher crude also lifts fuel costs for airlines, freight companies and consumers; Delta Air Lines reports September-quarter results on Friday, and fuel will be part of that discussion.

For the energy calendar:

• Today — EIA natural gas storage data at 10:30 a.m. ET.
• Friday into Saturday — Isaias' expected landfall on the northern Gulf Coast.
• After the storm — operator updates and regulator data on how much production has been restored.

The bottom line

Brent is back above $102 because two separate supply risks are pressing at the same time: a hurricane that has taken about a quarter of US Gulf oil output offline as a precaution, and renewed attacks on shipping near Hormuz. The first is likely to fade within days if the platforms escape damage. The second has no fixed end date, which is why the market is keeping a premium in the price.