 By early on August 31 , an increase in sustained winds , a decrease in barometric pressure , and a 23 miles ( 37 km ) wide eye observed by reconnaissance aircraft all suggested that Danielle was beginning to intensify . On August 31 , the anticyclone near Bermuda caused Danielle to curve northeastward , away from the East Coast of the United States . Later that day , a significant increase in intensity led the storm to again reach its maximum sustained wind speed of 105 mph ( 165 km / h ) . On September 1 , there was significant uncertainty in the future intensity of Danielle , as a shortwave trough located northeast of the storm would either enhance outflow , causing strengthening , or increase wind shear , resulting in weakening . At 1500 UTC on September 1 , it was predicted that Danielle would strengthen slightly before weakening and becoming extratropical by September 3 . Three hours later , Danielle reached its maximum sustained wind speed of 105 mph ( 165 km / h ) for the fourth and final time . 
