000 WTPZ41 KNHC 261437 TCDEP1 HURRICANE AMANDA DISCUSSION NUMBER 16 NWS NATIONAL HURRICANE CENTER MIAMI FL EP012014 800 AM PDT MON MAY 26 2014 Amanda has changed little during the past 6 hours, including an intermittent eye embedded within a ragged CDO feature containing cloud tops colder than -70C. A blend of final T-numbers and current intensity estimates from TAFB and SAB, and an ADT value of T6.3/122 kt, yields an average of 114 kt. Thus, the initial intensity of Amanda has been lowered to 115 kt for this advisory. Smoothing through the many fits and starts yields a 12-hour average motion of 345/04 kt, which is used for the advisory motion. Otherwise, there are no significant changes to the previous advisory track or reasoning. Amanda is expected to move slowly north-northwestward to northward between a broad mid-level trough to its west and a weak subtropical ridge situated to its east over Mexico for the next 72 hours or so. After which some slow erratic motion is possible when the cyclone is expected to weaken into a shallow system and become trapped within weak steering currents. The global and regional models are in good agreement on this developing scenario. As a result, the official forecast track is essentially just an update of the previous advisory track, and is close to the consensus model TVCE and the FSSE model. The deep-layer vertical wind shear across Amanda is assessed at around 25 kt by both the GFS-based SHIPS model and UW-CIMSS, and these strong shear conditions are expected to continue for at least the next 36 hours. As a result, steady to rapid weakening is forecast to begin later today, especially if significant cold upwelling develops beneath the slow-moving hurricane. The NHC intensity forecast is similar to the previous advisory, and closely follows the intensity consensus model IVCN. FORECAST POSITIONS AND MAX WINDS INIT 26/1500Z 13.2N 111.6W 115 KT 135 MPH 12H 27/0000Z 14.0N 111.9W 100 KT 115 MPH 24H 27/1200Z 14.9N 112.2W 85 KT 100 MPH 36H 28/0000Z 15.7N 112.4W 70 KT 80 MPH 48H 28/1200Z 16.1N 112.4W 55 KT 65 MPH 72H 29/1200Z 16.8N 112.1W 40 KT 45 MPH 96H 30/1200Z 17.1N 111.8W 30 KT 35 MPH 120H 31/1200Z 17.3N 111.8W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Stewart