000 WTPZ42 KNHC 262002 TCDEP2 HURRICANE SANDRA DISCUSSION NUMBER 13 NWS NATIONAL HURRICANE CENTER MIAMI FL EP222015 200 PM MST THU NOV 26 2015 Sandra's satellite presentation features a large CDO and impressive outflow in the northern semicircle. However, increasing shear has begun to restrict outflow in the southwestern quadrant. The initial intensity has been lowered to 105 kt based on a blend of the latest Dvorak Final-T and CI numbers (T5.0/6.0) from TAFB and SAB. Further quick weakening is expected as the shear is forecast to increase to about 35 kt in 24 hours and 50 kt by 48 hours. This should result in Sandra's low-level circulation becoming decoupled as the mid- and upper-level warm core is sheared off to the northeast. The new NHC intensity forecast closely follows the latest SHIPS model guidance, and shows Sandra weakening to a remnant low by 48 hours. A 72-h point is shown for continuity, but the low-level center of Sandra should dissipate quickly after it moves inland over mainland Mexico after 48 hours. Sandra has moved a little to the left of the previous forecast track, with an initial motion of 360/10. The track model guidance has shifted to the left this cycle, and keeps Sandra on a northward heading for the next 12 to 24 hours before turning north- northeastward between a mid-level ridge over Mexico and a broad deep-layer trough over western North America. The new NHC track has been adjusted 30-45 n mi to the left given the initial motion and the trend in the guidance, and now brings the center of a weakening Sandra closer to the southern tip of the Baja California peninsula in 36-48 hours. The NHC forecast is close to the new latest multi- model consensus. Given the updated forecast, the government of Mexico has issued a tropical storm watch for the southern tip of the Baja California peninsula from Todos Santos to Los Barriles. Note that the remnant mid/upper-level moisture associated with Sandra will contribute to a significant precipitation event expected to occur over portions of the south-central United States this weekend. For more information on this event, please see products from the NOAA Weather Prediction Center and local NWS Weather Forecast Offices. FORECAST POSITIONS AND MAX WINDS INIT 26/2100Z 16.8N 110.1W 105 KT 120 MPH 12H 27/0600Z 18.1N 110.2W 85 KT 100 MPH 24H 27/1800Z 19.8N 110.1W 65 KT 75 MPH 36H 28/0600Z 21.8N 109.5W 45 KT 50 MPH 48H 28/1800Z 24.2N 108.7W 30 KT 35 MPH...POST-TROP/REMNT LOW 72H 29/1800Z 27.0N 107.5W 15 KT 15 MPH...POST-TROP/INLAND 96H 30/1800Z...DISSIPATED $$ Forecaster Brennan