* Asian spot LNG prices down 60 pct since 2014
* Industry expects worse to come as output soars and demand slows
* El Nino to cause mild winter, further dent demand
* LNG could rival coal, iron ore as worst performing commodity
By Henning Gloystein and Jacob Gronholt-Pedersen
SINGAPORE, Aug 31 (Reuters) - Asian liquefied natural gas (LNG) prices could fall a further 25 percent in coming months as new supply, falling demand and weaker oil prices put it on par with iron ore and coal as the worst performing commodity of recent years.
Asia's LNG market has already fared worse than slumping oil markets, with spot prices LNG-AS down 60 percent since 2014 to $8 per million British thermal units (mmBtu), ending half a decade of high prices.
Australia's biggest energy firm, Woodside Petroleum WPL.AX , in August reported a 40 percent slide in first-half profits and said it expected LNG prices to remain low into 2016.
Ratings agency Moody's said on Monday it expected Woodside's credit metrics "to deteriorate substantially from its previously very strong levels."
LNG prices look to have further to fall.
While crude demand remains strong, research group Energy Aspects estimates Asian LNG imports fell 8.5 percent in the first half of 2015 from the same time last year, as the region's economies slow.
Add to the mix El Nino, which usually means milder winters in northern Asia, and a unique cocktail for falling prices may appear.
"The traditional power houses in north Asia are all showing signs of (demand) weakness at a point when there is lots of supply coming on to the market," said Neil Beveridge of Bernstein Research.
China's LNG imports have slumped from double digit growth in recent years to a three percent fall in the first half of 2015 from a year earlier.
For Japan, the world's top LNG importer, the restart of its nuclear power plants is eating away at LNG's market share in an environment of generally falling energy demand.
Imports into South Korea have also fallen due to a slowing economy and rising nuclear power output.
The slowing demand comes just as output soars. Following $200 billion of investments into LNG projects, Australia's exports are soaring, tripling its capacity to 86 million tonnes before 2020, which would make it the world's biggest LNG exporter ahead of Qatar.
Australia's soaring output comes at the same time as the United States starts exporting for the first time towards the end of this year.
A 25 percent fall in oil prices since June is adding to LNG weakness.
"The latest leg down in oil prices is in the process of feeding through into gas prices," consultancy Timera Energy said, as oil-indexation in LNG contracts meant crude movements would be priced into LNG with several months delay.
Analysts and traders said Asian LNG prices could fall to $6 per mmBtu, representing a 70 percent price drop since 2014 and putting it in the same league as coal and iron ore.