 At 12 : 00 UTC on September 11 , Humberto reached hurricane status while turning northward . About six hours later , it peaked with sustained winds of 90 mph ( 150 km / h ) . By late on September 12 , increasing wind shear , cooling sea surface temperatures , and a more stable atmosphere led to a weakening trend of the storm . Around 12 : 00 UTC on the next day , Humberto fell to tropical storm intensity , while curving west @-@ northwestward in the low @-@ level flow south of the Azores surface high pressure . Early on September 14 , the storm degenerated into a remnant low . However , deep convection began re @-@ developing later that day . At 00 : 00 UTC on September 15 , Humberto regenerated into a tropical storm about 1 @,@ 095 mi ( 1 @,@ 760 km ) southwest of Ponta Delgada , Azores . An approaching mid- to upper @-@ level cyclone began to capture Humberto , causing the storm to decelerate between late on September 16 and early on September 17 . When Humberto 's low @-@ level circulation became vertically stacked under the non @-@ tropical cyclone , the system transitioned into a subtropical storm on September 17 . Humberto then weakened to a subtropical depression early the next day , about 1 @,@ 120 mi ( 1 @,@ 800 km ) south of Ponta Delgada . The subtropical depression continued north @-@ northwestward until degenerating into an open trough , and was soon absorbed by a cold front . 
