Oil seesawed on Friday while the price of heating oil jumped more than 6 percent as severe winter cold crimped output at three U.S. refineries, raising worries about higher crude supplies and a possible squeeze on refined products.
The March contract in U.S. crude, which will go off the board today, settled 82 cents lower, at $50.34 a barrel.
Benchmark Brent crude for April was flat at $60, after falling to a week low of $57.80 on Thursday.
"It's sell crude, buy products today," said Dominick Chirichella, senior partner at the Energy Management Institute in New York. "The issues with the East Coast refiners have certainly been weighing on the market."
At least three refineries that account for more than two-thirds of the U.S. East Coast's output experienced significant disruptions due to single-digit temperatures that sent the entire Northeast into a deep freeze.
Short-covering in U.S. crude futures ahead of the expiry of the front-month contract could support oil in Friday's late trade, traders said after expectations for another big weekly drop in the U.S. oil rig count failed to materialize.
The number of rigs drilling for oil in the United States fell by 37 this week, the smallest weekly drop this year, a survey showed on Friday. The rig count itself was at its lowest in more than three years.
Brent's premium to U.S. crude widened to above $9 a barrel, the biggest gap in nearly six months.
U.S. heating oil surged more than 6 percent to $2.1368 a gallon, its highest since early December.
The heating oil rally came after Phillips 66 began experiencing extended delays in restarting a crude unit at its 238,000-barrel-per-day Bayway refinery in Linden, New Jersey, according to person familiar with the facility's operations.
In Trainer, Pennsylvania, Delta Refinery said the facility's cooling system, which normally draws water from the Delaware River, is partly frozen, and it had shut a fluid catalytic cracking unit.
Intelligence group Genscape reported that Philadelphia Energy Solutions Inc shut down a vacuum distillation unit at the Girard Point section of the 335,000 bpd refinery in Philadelphia.