ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM HURRICANE HILDA DISCUSSION NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102015 800 PM PDT FRI AUG 07 2015 The hurricane continues to intensify at a rapid pace. An earlier AMSR-2 microwave overpass revealed that Hilda's inner core was extremely compact. In addition, visible and infrared geostationary satellite imagery indicates that the system's eye has become better defined, and the areal extent of cold cloud-top temperatures surrounding the eye has increased over the past several hours. The current intensity estimate is raised to 90 kt, in accordance with a Dvorak estimate from TAFB. There is strong upper-level outflow associated with the cyclone, particularly over the western semicircle of the circulation. Hilda's intensification is forecast to continue over the next 12 to 24 hours, while vertical wind shear is expected to remain weak. In about 48 hours, the hurricane is forecast to begin encountering stronger shear associated with an upper-tropospheric trough near the Hawaiian Islands. Global models predict that the shear will increase greatly beyond 72 hours. Therefore a weakening trend is forecast to commence in 48 hours, with rapid weakening likely in the latter part of the forecast period. The official intensity forecast is in good agreement with the latest SHIPS and LGEM guidance. The initial motion estimate is slightly north of due west, or 280/13 kt. The track forecast reasoning has not changed much since the last advisory. Hilda's track should gradually bend toward the west-northwest and northwest over the next 96 hours or so, as the cyclone moves to the south of a mid-level ridge and approaches a cyclonic circulation just to the north of the Hawaiian Islands. Near the end of the forecast period, the rapidly weakening system should become a more shallow circulation, and turn more toward the west within the low- to mid-tropospheric flow. The official track forecast is in good agreement with the latest dynamical model consensus. Since Hilda will be moving into the central Pacific basin very soon, future information on this system will be issued by the Central Pacific Hurricane Center in Honolulu, Hawaii. FORECAST POSITIONS AND MAX WINDS INIT 08/0300Z 13.0N 139.6W 90 KT 105 MPH 12H 08/1200Z 13.4N 141.4W 100 KT 115 MPH 24H 09/0000Z 14.1N 143.5W 110 KT 125 MPH 36H 09/1200Z 14.9N 145.4W 110 KT 125 MPH 48H 10/0000Z 15.8N 147.2W 95 KT 110 MPH 72H 11/0000Z 17.8N 149.5W 75 KT 85 MPH 96H 12/0000Z 19.5N 151.0W 50 KT 60 MPH 120H 13/0000Z 20.6N 153.0W 35 KT 40 MPH $$ Forecaster Pasch NNNN