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#828094 (Received by flhurricane at: 3:44 AM 15.Jan.2016) TCDAT1 HURRICANE ALEX DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012016 500 AM AST FRI JAN 15 2016 The overall convective pattern of Alex has continued to erode since the previous advisory. However, conventional and microwave satellite imagery indicate that there is still enough inner-core convection and a small radius of maximum winds to warrant keeping Alex as a hurricane for this advisory. Satellite classifications continue to decrease, and the initial intensity has been lowered to 65 kt based on a blend of the TAFB current intensity estimate of T4.5/77 kt and a current T-number of T3.5/55 kt. Alex has yet to make the turn toward due north, and the initial motion estimate is 005/20 kt. Other than to nudge the forecast track slightly to the right based on the more eastward initial position, there are no significant changes to the previous forecast track or reasoning. Alex is expected to be steered northward and then northwestward over the next couple of days within deep cyclonic flow in the eastern periphery of a large extratropical low centered over the northwestern Atlantic near Newfoundland. On the forecast track, the center of Alex and the core of strongest winds should reach the central Azores by late morning or early afternoon. The global and regional model guidance remains in excellent agreement on this scenario, and the official forecast track is a blend of the consensus model TVCN and input from the Ocean Prediction Center. Most of the coldest cloud shield has now shifted into the western semicircle, a signal that extratropical transition is likely beginning. With Alex now moving over 16C sea-surface temperatures, and with colder water still ahead of the cyclone, transition to an extratropical cyclone should be complete within the next 12 hours. However, global models suggest that there will be enough baroclinic forcing to maintain hurricane-force winds after transition occurs despite the cold waters of the north Atlantic. The 34-kt wind radius was expanded in the northeastern quadrant based on quality wind reports from ship BATFR17. The wind field is expected to continue to expand as Alex undergoes extratropical transition at higher latitudes. The wind radii forecasts are based primarily on guidance from the NOAA Ocean Prediction Center. FORECAST POSITIONS AND MAX WINDS INIT 15/0900Z 36.8N 27.0W 65 KT 75 MPH 12H 15/1800Z 41.4N 27.7W 65 KT 75 MPH...POST-TROP/EXTRATROP 24H 16/0600Z 48.7N 30.0W 65 KT 75 MPH...POST-TROP/EXTRATROP 36H 16/1800Z 56.0N 34.5W 65 KT 75 MPH...POST-TROP/EXTRATROP 48H 17/0600Z 62.3N 37.7W 65 KT 75 MPH...POST-TROP/EXTRATROP 72H 18/0600Z...ABSORBED BY EXTRATROPICAL LOW $$ Forecaster Stewart |