000 WTPZ41 KNHC 040254 TCDEP1 HURRICANE VANCE DISCUSSION NUMBER 20...CORRECTED NWS NATIONAL HURRICANE CENTER MIAMI FL EP212014 700 PM PST MON NOV 03 2014 Corrected text to read tropical storm watch issued Vance has maintained a well-defined central dense overcast pattern since the previous advisory, although the eye has become less distinct in infrared and recent SSMI/S microwave imagery. However, cloud tops colder than -80C now completely encircle the remnant eye feature in infrared imagery. An average of Dvorak current intensity estimates yields a value of 96 kt, so the initial intensity is being maintained at 95 kt. Vance has started to recurve to the north-northeast and the initial motion estimate is now 020/11 kt. The hurricane is expected to move in a general north-northeastward to northeastward direction within south-southwesterly steering flow between the subtropical ridge to the east and an approaching deep-layer trough to the west. As a result, Vance is expected to pass just east of Socorro Island tonight and be near the southwestern coast of Mexico in 48 hours or so. The NHC model guidance is in decent agreement on this scenario, and the official forecast track is just an update of the previous advisory track and lies close to the blend of the GFS and ECMWF model solutions. The latest SHIPS guidance indicates south-southwesterly vertical wind shear of at least 30 affecting Vance. Although this estimate could be a little overdone given the impressive infrared satellite signature, a 0134 UTC SSMI/S microwave overpass suggests that the circulation is starting to tilt downstream to the northeast due to the shear. The vertical shear is forecast by all of the global models to steadily increase throughout the forecast period, which should result in steady or rapid weakening until landfall occurs in about 48 hours. The official intensity forecast is similar to the previous advisory and is close to a blend of the SHIPS and LGEM models, which is just slightly above the consensus model ICON. The forecast still calls for Vance to become a tropical depression just offshore of the coast of southwestern Mexico. However, due to the uncertainty in the exact timing of the expected weakening trend, the Government of Mexico has issued a tropical storm watch for portions of southwestern mainland Mexico. Moisture from Vance and its remnants should spread northeastward across Mexico and into the south-central United States during the next several days. This is likely to produce heavy rains over portions of these areas through Thursday or Friday. FORECAST POSITIONS AND MAX WINDS INIT 04/0300Z 17.4N 110.6W 95 KT 110 MPH 12H 04/1200Z 18.8N 110.1W 75 KT 85 MPH 24H 05/0000Z 20.5N 109.1W 60 KT 70 MPH 36H 05/1200Z 22.7N 108.3W 45 KT 50 MPH 48H 06/0000Z 24.6N 107.9W 30 KT 35 MPH 72H 07/0000Z 25.5N 108.1W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 08/0000Z...DISSIPATED $$ Forecaster Stewart