 With a subtropical ridge in the vicinity of the Marianas Islands , the nascent depression moved to the northwest . On August 3 , the JMA upgraded the depression to tropical storm status , naming it Etau . An upper @-@ level low to the northeast improved northerly outflow , allowing the storm to strengthen quickly . On August 4 the Philippine Atmospheric , Geophysical and Astronomical Services Administration ( PAGASA ) began issuing advisories as the storm approached the region , naming it Kabayan . Late on August 4 , the JMA upgraded Etau to typhoon status , with the storm later developing an eye . An approaching shortwave trough weakened the ridge , causing Etau to turn more to the north . At around 0030 UTC on August 7 , the typhoon made its closest approach to Okinawa , passing within 120 km ( 75 mi ) , and close enough for the 100 km ( 60 mi ) wide eye to cross over the island . Later that day , the JMA estimated peak maximum sustained winds of 155 km / h ( 100 mph ) , sustained over a duration of 10 minutes ; the JTWC estimated 1 minute winds of 205 km / h ( 125 mph ) . 
