Hurricane Isaias Forces Nearly Two-Thirds of U.S. Gulf Oil Output Offline

*Updated 14:43 UTC: Developing story.*

NEW ORLEANS: Hurricane Isaias, the first hurricane of the 2026 Atlantic season, forced the most dramatic single-day escalation of Gulf of Mexico shut-ins in years on Thursday, with federal figures showing nearly two-thirds of the region's offshore oil production taken offline as the storm churned toward the northern Gulf Coast.

Shut-ins jump in a day

According to the Marine Minerals Administration, operators shut in about 1.3 million barrels per day of oil output on Thursday, roughly 63 percent of the Gulf's daily production, along with about 1.1 billion cubic feet per day of natural gas, or around 57 percent of the region's gas output. Personnel were evacuated from 121 production platforms, nearly a third of the 371 manned platforms in the Gulf; workers were also removed from five of eleven non-dynamically positioned rigs, while four dynamically positioned rigs moved off location as a precaution.

The jump was striking. On Wednesday, only about 25 percent of the region's oil output and 16 percent of its natural gas production had been shut in. Shell, Chevron and BP were among the major operators evacuating non-essential personnel from platforms and curtailing production, according to reports.

Storm strengthens on approach

The National Hurricane Center's 10 a.m. CDT advisory Thursday put Isaias's maximum sustained winds at 85 miles per hour, with the storm centered about 380 miles south of the mouth of the Mississippi River and moving east-northeast at 10 miles per hour.

Forecasters expect landfall late Friday or early Saturday. Current projections place it somewhere between southern Alabama and the Florida Panhandle, while some forecasts call for the storm to come ashore east of New Orleans, a track that would spare the worst of the Gulf Coast's refining concentration from the storm's strongest winds. The forecast track and timing remain subject to change.

The National Weather Service warned of a life-threatening storm surge from the mouth of the Mississippi River to Suwannee, Florida, urging residents in the warning area to follow advice from local officials.

Refineries in the cone's path

The bigger anxiety for energy markets is what happens onshore. Gulf Coast refineries are running at high rates to make up for war-driven outages overseas, fuel inventories are already tapped, and the U.S. emergency oil stockpile sits at its lowest level since 1982. "Could be a gigantic event. It's the worst time something like this could happen in 25 years," Robert Yawger, director of energy futures at Mizuho Securities, said of the storm.

A landfall east of New Orleans would spare vital refining infrastructure, but any westward shift in the hurricane's cone of uncertainty could put major Gulf Coast refineries in harm's way. Analysts estimate that millions of barrels per day of refining capacity sit within or near the projected path.

Markets react

Oil prices rose about 4 percent on Thursday as supply disruptions mounted. A model from consulting firm Earth Science Associates estimates Isaias could erase roughly 9 million barrels of Gulf oil production, a marked increase from the 7.1-million-barrel hit inflicted by Tropical Storm Bertha in July. The firm lists BP, Chevron, ENI, Murphy Oil and Shell as the companies with the most exposure to the storm.

The federal offshore Gulf of Mexico produces about 2 million barrels of oil a day, roughly 15 percent of total U.S. crude output, along with about 2.1 billion cubic feet per day of natural gas.

What comes next depends on the storm's path and intensity. Operators will watch the landfall zone for damage to platforms and onshore facilities, and markets will watch for refinery outages and restart timelines.