* Sugar market awaits crush update from Brazil's Unica
* Arabica coffee prices seen rangebound in short-term
* Cocoa market underpinned by improved grinding outlook
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LONDON, Oct 24 (Reuters) - ICE raw sugar turned higher on Wednesday, lifting off a three-week low as traders positioned themselves ahead of a report from Brazilian cane industry association Unica due later in the day.
Arabica coffee futures on ICE were slightly lower as the market struggled to consolidate above recent lows while cocoa prices were also weaker.
Unica is due to provide an update on crop progress up to mid-October with the market keen to know the extent to which drier weather has boosted production.
``I think there's a lot of pre-emptive trading beforehand, traders do tend to buy or sell the rumour and the reverse when the figure comes out,'' one London dealer said.
March raws were up 0.13 cent or 0.7 percent at 19.78 cents a lb at 1401 GMT after earlier falling to a three-week low of 19.45 cents.
``We suspect it will show a higher output than was expected two weeks ago as weather has been drier than expected. The impact may already be written into prices, so we do not discount a bounce on the release,'' Nick Penney of Sucden Financial said in a market note.
December white sugar on Liffe was up $6.60 or 1.2 percent at $548.60 per tonne.
Arabica coffee futures on ICE were slightly lower with the market look set to remain rangebound in the near term.
December arabicas were off 0.60 cent or 0.4 percent at $1.6025 per lb.
The contract hit $1.5715 last week, the lowest level for the front month since Sept. 6.
``Some European roasters will have to come into (physical) markets to buy, but that might impact differentials as opposed to futures. So we'll still be rangebound in the short term,'' Macquarie analyst Kona Haque said.
New York December coffee looks neutral in a range of $1.5715 to $1.6385 per lb, and only an escape could point to a future direction, according to Wang Tao.
ICE certified arabica stocks continued their steady climb, reaching 2.36 million bags, as of October 23.
January robusta coffee futures were off $5 or 0.2 percent at $2,053 a tonne.
Cocoa futures were lower with the market slipping back from highs set early this week.
ICE December cocoa was down $31 or 1.2 percent at $2,467 per tonne, having on Monday touched $2,526, the highest level since late September.
New York December cocoa will retrace to $2,432 per tonne as it did not break a resistance at $2,523 per tonne, according to Reuters analyst Wang Tao.
The market has derived support from an expected rebound in grindings in the current quarter and in early 2013 following weak data for the second and third quarters of this year.
Dealers were also keeping a close watch on the flow of cocoa out of West Africa following the start of main crop seasons earlier this month, particularly in view of major reforms in top grower Ivory Coast.
``We've not convinced supply is going to come as easily as people expected. Rains in West Africa may hamper drying activity, we're not seeing so much activity in bushels and middle men are trying to sort out finances,'' Haque said.
Liffe March cocoa futures were off 23 pounds or 1.4 percent at 1,600 pounds per tonne.
(Reporting by Nigel Hunt; editing by William Hardy and Jason Neely)