RUBBER — Japan futures hit 15 — year high on firm raw material costs, Ivory Coast port congestion

By Emily Ou Yong Sept 24 (Reuters) — Japanese rubber futures surged to a 15-year high on Thursday as the market reopened after a three-day holiday, driven by firm raw material costs and supply concerns caused by port congestion in one of the top rubber producers, Ivory Coast. The Osaka Exchange (OSE) rubber contract for February delivery was up 21.5 yen, or 5%, at 451.7 yen ($2.86) per kg as of 0230 GMT. It touched its highest since April 13, 2011. The market was closed on Monday through Wednesday for a holiday. The rubber contract on the Shanghai Futures Exchange (SHFE) for January delivery rose 285 yuan, or 1.49%, to 19,405 yuan ($2,889.02) per metric ton, its highest since September 10. The most active November butadiene rubber contract on the SHFE surged 550 yuan, or 3.71%, to 15,380 yuan per metric ton. A Singapore-based rubber trader said the rally has been driven by a combination of factors, including the impact of El Niño, congestion at Ivory Coast's Abidjan port, and reduced raw material supplies, all of which have tightened the supply-demand balance. Top rubber producer Thailand's meteorological agency warned of severe rains and flash floods from September 23 to 27. Rubbe