Typhoon Yutu is unleashing a likely catastrophic blow to US islands in the western Pacific Ocean. Rains and winds are pounding the island of Guam with sustained winds of 290 km/h. The storm is roaring across the U.S. islands of Saipan and Tinian, part of the Mariana island chain. The US National Weather Service chorded a super typhoon equivalent to a Category 4 or 5 hurricane. Authorities have issued typhoon warnings and tropical storm warnings.