SOFTS-Robusta rises to 2-1/2-mth high, Liffe cocoa board inverts

* Vietnam December coffee shipments exceed expectations

* Raw sugar hovers just above last month's 2-year low

* Cocoa market awaits North America grind data at 2100 GMT

(Updates closing coffee/sugar prices)

NEW YORK/LONDON, Jan 17 (Reuters) - Robusta coffee futures on LIFFE rose to their priciest in 2-1/2 months on Thursday, boosted by strong roaster demand which has helped absorb greater-than-expected shipments from Vietnam.

London's nearby cocoa contract surpassed some deferred prices, a forward curve structure known as "backwardation" that arose from supply concerns, while cocoa futures on ICE Futures U.S. went higher as dealers awaited the North American cocoa grindings data due after the market closes.

Arabica coffee climbed as well, while raw sugar turned lower late in the session. The general firmness of the softs complex tracked the firm Thomson Reuters-Jefferies CRB index, a global benchmark for commodities, which jumped to a 1-1/2-month high as crude oil climbed more than 1 percent.

Better-than-expected U.S. housing and labor market data signaled strength in the world's largest economy, providing positive macro sentiment.

Gains on robusta coffee futures are expected to be capped by origin selling as higher prices attract Vietnamese sellers in the weeks leading up to the Tet holiday in February.

March robusta coffee futures rose $9, or 0.5 percent, to settle at $1,978 a tonne, after earlier rising to $1,988, the highest level for the second-month since Nov. 2.

Vietnam's coffee exports rose a third in December from the previous month to 162,500 tonnes, or 2.7 million bags, the customs department said, beating market expectations.

"The shipment figures are very good, without a doubt," a European analyst said.

However, dealers said the crop may tail off earlier than expected after a strong start, sending a bullish signal to the market.

Vietnam is in the midst of harvesting its second consecutive bumper crop, which traders expect to fall slightly short of the record output seen in 2011/12.

ICE March arabica coffee finished up 2.50 cents, or 1.6 percent, at $1.5550 per lb.

Dealers monitored reports of coffee leaf rust in Central American countries but said it was too soon to mark down any production estimates.

Also providing a lift was a boost in call buying of March arabica options at $1.70 per lb, giving spillover support to futures, dealers said.

Cocoa futures on Liffe were firm, with a lift from the weak pound against the U.S. dollar, with the spot contract climbing to a small premium against the second position for the first time since Dec. 10.

"There's only about 40,000 tonnes of certified stock in London so I think that is being used as a positive to get the market up," said Nick Gentile, chief trader at Atlantic Capital Advisors in New Jersey.

London May cocoa futures settled up 24 pounds, or 1.6 percent, at 1,481 pounds per tonne, a discount of 8 pounds to the spot March contract, pushing the price structure into backwardation.

ICE March cocoa futures rose $44, or 2 percent, to close at $2,300 per tonne.

WEAK MARGINS

"In view of weak margins, chocolate producers have been increasingly resorting to their own stocks in recent months - now these will have to be replenished," Commerzbank said in a daily commodities note.

It said the corresponding data due later Thursday for North America "are likely to be better than the figures in Europe, where demand was additionally hit by the economic crisis."

The bank also said producer countries were playing an increasingly important role in terms of grinding and therefore it was misleading to focus solely on the traditional consumer countries.

The market awaited the North American fourth quarter grinding data, with expectations ranging from 5 percent lower to 1 percent higher. The data is scheduled for release after the market closes at 4 p.m. EST (2100 GMT).

"Cocoa fundamentals are mildly constructive. From the current levels of $2,200 we would expect the market to move up to the $2,400 per tonne levels," Macquarie analyst Kona Haque said on a conference call.

"The market is carrying a small deficit of 80,000 tonnes on the back of lower production in Indonesia, Ghana and the Ivory Coast where weather has been less than ideal and at the same time we are also expecting a modest recovery in grindings."

Several regions have reported fourth quarter grindings data, including Europe, where quarterly grindings fell by 6.2 percent partly due to poor processing margins.

March raw sugar futures on ICE changed direction and turned down 0.03 cent, or 0.2 percent, to close at 18.42 cents per lb, remaining within striking distance of a two-year low of 18.31 hit in December amid a large global surplus.

March white sugar on Liffe eased $2.10, or 0.4 percent, to end at $497.50 per tonne.

(Additional reporting by Nigel Hunt in London; editing by James Jukwey, Grant McCool and Alden Bentley)