ZCZC MIATCDEP4 ALL TTAA00 KNHC DDHHMM TROPICAL DEPRESSION NINE-E DISCUSSION NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP092016 200 PM PDT SUN JUL 31 2016 Visible satellite imagery showed a low-level cloud swirl emerge from the convective canopy after the previous advisory was issued. However, for now it appears that this was not the primary center of the cyclone, as it has dissipated and low cloud lines continue to suggest a center closer to the convection. Given the somewhat disorganized nature of the system for now, the initial intensity is held at 30 kt in agreement with the latest Dvorak estimate from SAB. The SHIPS model analysis shows about 10 kt of north-northwesterly shear over the depression, which is consistent with the convection being displaced mainly to the south and east of the center. This shear is expected to relax a little, but the cyclone will only be over SSTs above 26C for the next 36 hours or so. This should allow for some strengthening, followed by gradual weakening to post- tropical status over cool waters and in a dry, stable atmospheric environment in about 3 days. The new NHC intensity forecast is similar to the previous one, and close to the IVCN consensus aid. The uncertainty in the center position leads to an uncertain initial motion estimate of 295/09, which is based in part on continuity. Despite this, the track forecast reasoning remains relatively straightforward, as a mid-level ridge is expected to build westward to the north of the cyclone through the forecast period. This should result in a west-northwestward heading and an increase in forward speed over the next 48 hours. After that time, the track should gradually bend back toward the west as the increasingly shallow cyclone comes under the influence of the low-level trade winds. The NHC track forecast is about 40 n mi north of the previous one due to the adjustment in the initial position, but is otherwise near the middle of the guidance envelope and the TVCN multi-model consensus. FORECAST POSITIONS AND MAX WINDS INIT 31/2100Z 15.4N 121.2W 30 KT 35 MPH 12H 01/0600Z 15.9N 122.6W 35 KT 40 MPH 24H 01/1800Z 16.7N 124.8W 40 KT 45 MPH 36H 02/0600Z 17.8N 127.2W 45 KT 50 MPH 48H 02/1800Z 19.1N 129.9W 45 KT 50 MPH 72H 03/1800Z 21.1N 135.5W 35 KT 40 MPH 96H 04/1800Z 22.4N 140.8W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 05/1800Z 23.0N 146.5W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Brennan NNNN