 Karina was located to the south of a weakening mid @-@ level ridge , leading to a relatively slow west @-@ northwest movement at 9 mph ( 15 km / h ) . Upon becoming a tropical storm , Karina reached its peak with winds of 40 mph ( 65 km / h ) . There was uncertainty as to the intensity of the storm , as the Dvorak technique — a system used to estimate the intensity of a tropical cyclone — rendered an intensity of 50 mph ( 80 km / h ) ; but because the center of the storm had just moved under the deep convection , the winds were held at minimal tropical storm intensity . That night , 12 hours after being declared a tropical storm , Karina was downgraded to a tropical depression . Strong easterly wind shear of at least 25 mph ( 40 km / h ) tore away the deep convection that previously surrounded Karina . Karina was moving into a stable environment over cooling waters which would prevent convection from redeveloping , despite a forecast of lessening wind shear . The forward motion gradually decreased . By the morning of September 3 , convection had been sheared 125 mi ( 200 km ) from the center of circulation , leaving only a swirl of clouds . Karina degenerated into a remnant low @-@ pressure area later that morning and the NHC issued their final advisory . The remnant low quickly dissipated that afternoon . 
