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By Robert Gibbons
NEW YORK, Aug 12 (Reuters) - The premium for U.S. gasolineprices over benchmark crude has surged by more than $6 in threedays, its biggest such rise in more than four years, as a seriesof refinery disruptions toward the end of an unusually strongsummer driving season squeeze supplies.
U.S. RBOB gasoline futures jumped more than 4 percenton Wednesday, even as U.S. crude futures barely gained0.5 percent, widening the so-called crack spread between the twoto $31 a barrel intraday - nearly the highest level since 2013.
Before this week, the spread had slipped to below $25 abarrel, near its lowest since February, as U.S. gasolineinventories remained at relatively comfortable seasonal levelsand dealers anticipated a seasonal slowdown in demand.
That changed in recent days, with at least three majorrefineries experiencing serious upsets that will cut intogasoline production, with weeks of summer demand to go. Somedealers are betting the rally will continue.
"Spreading opportunities are obvious and we continue tofavor long gas (gasoline) cracks that appear poised for new wideterritory," Jim Ritterbusch, president at Ritterbusch &Associates in Galena, Illinois, said in a note to clients.
A 240,000-barrel per day (bpd) crude unit outage at BP Plc's413,500-bpd Whiting, Indiana, refinery on Saturday, expected tolast at least a month, has helped boost gasoline futures alongwith an gasoline making unit outage at Philadelphia EnergySolutions' refinery in Philadelphia and another at Phillips 66'sBayway, New Jersey, plant.
On Wednesday, government data showed the country's gasolineinventories fell 1.25 million barrels last week
As of midday on Wednesday, gasoline futures had surged morethan 8 percent this week, while U.S. crude futures havefallen by more than 1 percent.
The gasoline crack spread <1RBc1-CLc1>
