ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM HURRICANE SEYMOUR DISCUSSION NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL EP202016 200 PM PDT TUE OCT 25 2016 Seymour has continued to intensify since the last advisory, with the 15 n mi wide eye continuing to become better defined inside the central dense overcast. Satellite intensity estimates from TAFB, SAB, and the CIMSS satellite consensus are all 115 kt, so that is the initial intensity for this advisory. The hurricane currently has good cirrus outflow in all directions except to the south. Seymour is expected to remain within an area of low wind shear and over SSTs of around 28C for the next 12-18 hours, and thus some additional strengthening is possible. After 18 hours, increasing southwesterly shear and cooler waters should cause steady to rapid weakening. The majority of the guidance continues to show Seymour weakening below hurricane strength in less than 72 hours, degenerating to a remnant low by 96 hours, and dissipating completely by 120 hours. The new intensity forecast is an update of the previous forecast and again lies near the upper end of the intensity guidance. The initial motion is still 275/12. A mid- to upper-level ridge extending westward from Mexico is expected to steer Seymour westward to west-northwestward for another 12-24 hours. Subsequently, a deep-layer trough over the northeastern Pacific is expected to cause a break in the ridge, with Seymour turning northwestward and northward into the break. Most of the track guidance suggests the forward motion should slow after 48 hours as Seymour shears apart, and it now suggests that the hurricane should turn more westward before dissipation as it is steered by low-level easterly flow. The new forecast track is similar to the previous track for the first 72 hours, then it is shifted a little westward at the 96 hour point. FORECAST POSITIONS AND MAX WINDS INIT 25/2100Z 15.7N 116.4W 115 KT 130 MPH 12H 26/0600Z 16.2N 118.2W 120 KT 140 MPH 24H 26/1800Z 17.2N 120.3W 110 KT 125 MPH 36H 27/0600Z 18.5N 121.7W 95 KT 110 MPH 48H 27/1800Z 19.9N 122.4W 80 KT 90 MPH 72H 28/1800Z 21.0N 122.5W 40 KT 45 MPH 96H 29/1800Z 21.5N 123.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 30/1800Z...DISSIPATED $$ Forecaster Beven NNNN