New York's main contract, light sweet crude for February slid 37 cents to $91.12.
Brent North Sea crude for delivery in February dropped 24 cents to 94.14 dollars a barrel in London trade.
"As long as the extreme cold in the northern hemisphere persists, this will lend some support to oil prices in the near term," said Barclays Capital analyst Chen Xin Yi. The United States is the world's biggest oil consuming nation.
There was further travel chaos in the US northeast on Wednesday after hundreds of flights were canceled and the region dug out from what some are calling "Snowpocalypse."
Oil prices had risen on Tuesday amid expectations of a fall in US energy stockpiles caused by the cold weather.
US reserves fell by about 15 million barrels in the first half of December in the face of brisk demand and end-of-year inventory adjustments by refiners.
New figures on US stocks are to be published Thursday.
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