Oil prices surged on Thursday, posting their biggest dollar increase in nearly eight months on concerns that a storm brewing in the Gulf of Mexico could impact oil production sites

Light, sweet crude for delivery in November settled at $2.58 higher at $82.88 per barrel on the New York Mercantile exchange. Meanwhile in London, the price of Brent North Sea crude for November delivery closed at $80.03 per barrel, up $2.60. It was the first time Brent crude has topped $80.

Investors still drove crude prices higher despite a U.S. government report released Wednesday stating that crude oil inventories had risen for the first time in nearly 9 weeks. Crude inventories rose by 1.8 million daily in the U.S, beating average analysts’ expectations of more than a 2 million barrel loss.

Another factor contributing to higher oil prices is ongoing weakness in the U.S. dollar, which allows foreign investors to make cheaper investments in dollar-denominated oil.

Meanwhile, last week’s decision by the Federal Reserve members to cut a benchmark interest rate by half a point may still be weighing on investors’ minds, raising the risk of inflation, sending crude higher.