** Shares of Whitehaven Coal WHC.AX fall as much as 6.2% to A$7.92, hitting their lowest level since January 12
** Stock set for weakest intraday trading session since January 30
** Australia's top independent coal miner swung to a surprise HY underlying net loss after tax of A$19 mln ($13.38 mln), compared with VA consensus estimate of a profit of A$16 mln
** Co declared interim dividend of 4 Australian cents per share
** Added plans to spend further A$32 mln on share buybacks over next 6 months
** YTD, stock up 2.5%, including the day's moves
($1 = 1.4198 Australian dollars)
(Reporting by Shivangi Lahiri in Bengaluru)
((shivangi.lahiri@thomsonreuters.com))