Refineries with output of at least 4.4 million barrels per day (bpd) were offline on Tuesday, representing almost 24 percent of United States production, according to Reuters estimates and company reports.
The expected USA crude build-up on Tuesday widened the WTI discount to Brent to $5.64 per barrel, its widest in over two years.
But global oil prices have continued to fall.
"Disruptions to refineries, production and trade will also make the weekly EIA data even noisier and less useful as a high frequency indicator at the very time OPEC needs it most", the Barclays note added.
The amount of production offline on Sunday was roughly 378,633 barrels of oil per day out of the roughly 1.75 million bpd pumped from the Gulf.More news: Destiny 2 PC beta starts today
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The refinery closures helped to push USA gasoline futures to a two-year high of $1.7799 per gallon on Monday, though they had receded to $1.7466 by 1325 GMT on Tuesday.
Preparing for more rain and floods, Total cut production in half at its 225,500 bpd refinery, also in Port Arthur.
"US gasoline prices increased by 3% at $1.8380 per gallon, the most since 31 July 2015".
The National Weather Service warned that rainfall may exceed a record-breaking 50 inches in areas around Houston. Tropical Storm Harvey, which has been downgraded from a hurricane, hit oil refiners harder than crude producers.
More than 18 percent of oil production in the Gulf of Mexico was shut in, the U.S. Department of the Interior's Bureau of Safety Environmental Enforcement said.
After settlement, industry group the American Petroleum Institute said its data showed that last week USA crude stocks fell, while gasoline inventories increased and distillate stocks drew.
"We are thus lowering our Brent oil price estimates to $55 per barrel from $60 per barrel in 4Q17 (and) to $57 per barrel from $64 per barrel in 2018", Jefferies bank said.