(Rewrites throughout, updates prices; adds comment, NEW YORK dateline) NEW YORK/LONDON, Aug 31 (Reuters) - New York cocoa futures on ICE rallied on Friday, on chart-based buying that helped lift its monthly gains to the strongest since April, while arabica coffee quietly extended losses in its weakest monthly performance in nearly two years. Raw sugar, arabica coffee and New York cocoa contracts will be closed on Monday for the Labor Day holiday.
* December New York cocoa settled up $61, or 2.7 percent, at $2,336 per tonne.
* The second-position contract closed August up 5.2 percent, its strongly monthly performance since April as weekly bean arrivals to ports in top grower Ivory Coast fell below year-ago levels.
* Prices were lifted by technical buying above support at $2,250 and month-end buying, traders said.
* December London cocoa settled up 29 pounds, or 1.8 percent, at 1,688 pounds per tonne. For the month, it closed up 2.7 percent, also its strongest monthly gain since April.
* December arabica coffee settled down 0.85 cent, or 0.8 percent, at $1.018 per lb, just above last week's 12-year low of 99.35 cents.
* It closed August down 10 percent, its biggest monthly drop
since November 2016, after the weaker currency in top
grower Brazil and expectations for a record crop there spurred heavy selling, traders said.
* "It's just following the (Brazilian) real down," said Shawn Hackett, president of Hackett Financial Advisors.
* The downside trend remains firmly intact, said Sucden Financial technical analyst Geordie Wilkes.
* "Despite weakening currencies in some of the world's larger coffee producers that offer some respite with the lower terminal markets, the costs of imported inputs such as fertilizer has increased not only in U.S. (dollar) terms but further impacted by the weaker currencies which could impact 2019-20 crop output," Volcafe Ltd said in a weekly report seen
* November robusta coffee settled down $21, or 1.4 percent, at $1,501 per tonne. The second-position closed the month down 8.3 percent, its weakest monthly performance since April 2017.
* Coca-Cola Co has agreed to buy coffee chain Costa,
taking on the likes of Starbucks and Nestle in
the booming global coffee market.
* October raw sugar settled up 0.03 cent, or 0.3 percent, at 10.6 cents per lb. It closed the month up 0.5 percent, after rebounding above last week's 10-year low.
* The prior session's rally generated chart-based buying, though any major recovery in prices could be limited by excess supplies, traders said.
* October white sugar settled up $1.60, or 0.5 percent, at $325.90 per tonne.
(Reporting by Marcy Nicholson in New York and Nigel Hunt in London; editing by David Goodman and Susan Thomas)