UPDATE 1-Australia's JB Hi-Fi shares jump, Jan sales strong

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SYDNEY Feb 11 (Reuters) - Shares in Australia's JB Hi-Fi Ltd jumped as much as 15 percent on Monday, the biggest one-day gain in four years, after the electronics retailer beat forecasts with a 3.1 percent rise in first-half profit.

JB Hi-Fi Chief Executive Terry Smart said the new year had got off to a positive start, with same-store sales in January up 4.2 percent from a year earlier.

He said he expects sales in the year to end-June 2013 to be around A$3.25 billion ($3.3 billion) and net profit after tax within the range of A$108.0 million to A$112.0 million, a rise of 7 percent.

Smart said sales of televisions remained a drag on total sales, as most consumers had already upgraded to flat-screen sets.

The company's shares were up 12.7 percent at A$12.41 at 0008 GMT, after hitting a one-year high of A$12.70.

Dealers said short-covering contributed to the share price spike, with retailers in general targeted by hedge funds betting on further price falls, and JB Hi-Fi's stock in particular the most heavily shorted retailer.

The latest weekly short-selling data from markets regulator the Australian Securities and Investments Commission showed that a hefty 18 percent of JB Hi-Fi's outstanding shares have been sold short. (Reporting by Jane Wardell and Victoria Thieberger; Editing by Richard Pullin)