SINGAPORE: Japanese rubber futures advanced for the ninth consecutive day on Friday, and logged the largest monthly rise in almost four years, buoyed by continued supply disruptions amid wet weather in top producer Thailand.

The Osaka Exchange (OSE) rubber contract for February delivery closed up 1.7 yen or 0.45%, at 375.6 yen ($2.59) per kg. The contract hit an intraday high of 380.3 yen earlier in the session, its highest since Aug. 8, 2011.

It gained 7.59% this week, its best since March, and 19.2% for the month its biggest month-on-month gain since October 2020. However, the January rubber contract on the Shanghai Futures Exchange (SHFE) fell 80 yuan or 0.48%, to finish at 16,640 yuan ($2,346.70) per metric ton.

Though the severity of rains and floods in Thailand has eased, continuing seasonal rains are expected to disrupt harvesting, and thus concerns over low availability in the usual season of peak supply are expected to continue holding prices firm, said Jom Jacob, chief analyst at Indian analysis firm What Next Rubber.

However, a drop in butadiene rubber prices, and potential caution from speculative traders awaiting key US inflation data and Chinese manufacturing PMI data, can weigh on natural rubber futures, Jacob added. SHFE rubber futures probably had some profit-taking before the weekend and technical trading, said Farah Miller, CEO of independent rubber-focused data firm Helixtap Technologies.

Thailand’s meteorological agency forecast less rains as the southwest monsoon prevailing over the country is weakening, but warned of possible flash floods from Sept. 1-5. The most active October butadiene rubber contract on the SHFE fell 130 yuan, or 0.85%, to 15,120 yuan ($2,132.34) per metric ton.

The front-month rubber contract on Singapore Exchange’s SICOM platform for September delivery last traded at 179.5 US cents per kg, down 0.8%.