TOKYO, Jan 30 (Reuters) - Japan's Nikkei share average tumbled on Thursday, at one point hitting a 2-1/2-month intraday low, as the U.S. Federal Reserve continued to scale back stimulus despite emerging market turmoil. A rise in the yen also soured overall sentiment. The Nikkei closed 2.5 percent lower at 15,007.06 after falling to as far as 14,853.83, the lowest since Nov. 14. The index's support is seen at 14,731.17, a 61.8 retracement from an October low to a December high. The broader Topix dropped 2.6 percent to 1,224.09.