Natural gas jumped to the highest price in five years as forecasters warned of more freezing U.S. weather. Hedge funds increased bullish bets on the heating fuel as inventories dropped to the lowest in a decade. Natural gas for March delivery gained as much as 5.8 percent to $6.493 per million British thermal units in electronic trading on the New York Mercantile Exchange, the highest intraday price since Dec. 2, 2008. Source