 After becoming a tropical storm , Imbudo passed about 35 km ( 20 mi ) north of Yap . The JMA upgraded Imbudo to a severe tropical storm late on July 18 , around the same time that the JTWC upgraded it to a typhoon . An increase in outflow to the south and to the north from a tropical upper tropospheric trough ( <unk> ) caused a 36 ‑ hour period of rapid development beginning on July 19 . During that time , the JMA upgraded Imbudo to typhoon status , the Philippine <unk> , <unk> and Astronomical Services Administration ( PAGASA ) began issuing advisories as the storm approached the Philippines , and a 30 km ( 20 mi ) wide eye formed . At 1200 UTC on July 20 , the JMA estimated peak 10 minute sustained winds of 165 km / h ( 105 mph ) . At the same time , the JTWC estimated 1 minute sustained winds of 240 km / h ( 150 mph ) , making it a super typhoon . By late on July 20 , the typhoon had developed concentric <unk> , and the <unk> was moving away , thus diminishing outflow . Imbudo maintained peak winds for about 12 hours , before the innermost eye contracted to a diameter of 11 km ( 7 mi ) in the midst of an eyewall replacement cycle . At 0300 UTC on July 22 , Imbudo struck northern Luzon , with 1 minute winds estimated at 205 km / h ( 125 mph ) by the JTWC . 
