COMMODITIES-17 pct gas gain leads index to 2nd straight monthly rise

NEW YORK, Jan 31 (Reuters) - The commodities complex had its second consecutive monthly gain in January as markets such as arabica coffee and heating oil finished up sharply on Friday to join the month's big winner, natural gas. Arabica prices rose 4 percent on the day to hit a six-month high. Heating oil has jumped about 4 percent over the past four sessions to reach a near 5-1/2 year peak. Natural gas fell more than 10 percent over the past two sessions, wiping out all of Wednesday's rally, which took it to a four-year high. Even so, gas finished at the top of the commodities table for January, rising 17 percent on the month as a brutally cold winter pushed demand for the heating fuel well past expectations. "Natural gas was really rocking this month," said Gene McGillian, energy analyst at Tradition Energy in Stamford, Connecticut. "Severely lower temperatures than expected and significant drop in gas inventories have all come together to push this rally the way we've seen." The front-month natural gas contract in New York settled at $4.943 per million British thermal units (mmBtu) versus December's finish of $4.230. Gas prices rose 26 percent for all of 2013. The Thomson Reuters/Core Commodity Index, a benchmark for global commodities made up of 19 components, finished up 1.1 percent for January and slightly lower for the session. It was the second month in a row that the CRB had risen after December's gain of nearly 2 percent. Arabica coffee, part of the "soft commodities" complex along with cocoa and raw sugar, posted the biggest monthly rise after gas. Arabica's most actively traded futures contract in New York, March, settled at $1.2520 per lb, up 4.3 percent on the day and 13 percent on the month. It hit a six-month high of $1.2595 earlier on Friday. Arabica rallied as concern over hot, dry weather in top coffee grower Brazil fueled speculative short-covering and even buying of new long positions, dealers said. March cocoa rose 7.5 percent on the month, settling at $2,911 a tonne versus $2,709 in December. Heating oil, also boosted by cold weather, rose 6.6 percent for January, settling at $3.279 per gallon. Prices at 3:40 p.m. EDT (2040 GMT)

LAST/ NET PCT CLOSE CHG CHG US crude 97.50 -0.73 -0.7% Brent crude 106.38 -1.57 -1.5% Natural gas 4.943 -0.068 -1.4% US gold 1240.10 -2.10 -0.2% Gold 1243.20 0.00 0.0% US Copper 3.20 -0.03 -0.9% LME Copper 7065.00 -30.00 -0.4% Dollar 81.282 0.197 0.2% CRB 283.312 -0.250 -0.1% US corn 434.00 1.00 0.2% US soybeans 1282.75 7.75 0.6% US wheat 555.75 2.25 0.4% US Coffee 125.20 5.20 4.3% US Cocoa 2911.00 -1.00 0.0% US Sugar 15.55 0.56 3.7% US silver 19.120 18.929 1.5% US platinum 1406.40 0.00 0.0% US palladium 703.20 -3.65 -0.5%

(Editing by Peter Galloway)