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#880419 (Received by flhurricane at: 3:42 AM 24.Nov.2016) TCDAT1 HURRICANE OTTO DISCUSSION NUMBER 14 NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016 400 AM EST THU NOV 24 2016 Otto continues to produce an area of deep convection over the center, but it is difficult to tell if there have been any structural changes to the cyclone without microwave or aircraft data overnight. Dvorak estimates at 06Z were T4.5/77 kt from SAB and T4.0/65 kt from TAFB, with the 06Z UW-CIMSS ADT estimate at 72 kt. The initial intensity is held at 75 kt for this advisory based on the higher satellite estimates and continuity. An Air Force Reserve Hurricane Hunter aircraft will investigate Otto later this morning. There is an opportunity for some additional strengthening before Otto makes landfall in about 12 hours. After landfall, quick weakening is expected while the center moves across Central America, and Otto is expected to emerge into the eastern Pacific by 24 h as a tropical storm. Gradual weakening is forecast after that time, due to moderate to strong vertical shear, and this weakening trend is also shown in most of the global model guidance. The new NHC intensity forecast is similar to the previous one and near the low end of the TC intensity guidance late in the period. This forecast ends up closest to the FSU Superensemble by day 5, and shows Otto as a remnant low at that time. The initial motion estimate is 270/07, as Otto is under the steering influence of a mid-level ridge centered over Cuba and the Bahamas. As as mid/upper-level trough lifts out of the Gulf of Mexico, the ridge will build westward and amplify during the next 3-4 days. This pattern should result in an increase in forward speed and a motion somewhat south of due west for the next 72 hours. By the end of the period, Otto or its remnant low should turn west-northwestward as it rounds the western side of the weakening ridge. While there is general agreement on this scenario, there remains some spread in the track guidance. In particular, the latest ECMWF solution has shifted north and is slower than the rest of the guidance, especially compared to the GFS, which is faster and farther south. The new NHC track forecast is largely an update of the previous one but trends a little faster following the latest consensus. This track is close to the ECMWF/GFS blend at days 3 through 5. FORECAST POSITIONS AND MAX WINDS INIT 24/0900Z 11.2N 82.9W 75 KT 85 MPH 12H 24/1800Z 11.1N 83.9W 75 KT 85 MPH...INLAND 24H 25/0600Z 10.6N 86.2W 50 KT 60 MPH...OVER WATER 36H 25/1800Z 10.2N 88.4W 45 KT 50 MPH 48H 26/0600Z 9.8N 90.9W 40 KT 45 MPH 72H 27/0600Z 9.5N 96.5W 40 KT 45 MPH 96H 28/0600Z 10.0N 101.5W 35 KT 40 MPH 120H 29/0600Z 11.5N 104.0W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Brennan |