000 WTPZ44 KNHC 162037 TCDEP4 Tropical Storm Carlotta Discussion Number 9 NWS National Hurricane Center Miami FL EP042018 400 PM CDT Sat Jun 16 2018 Satellite imagery and radar images from Acapulco Mexico suggest that there continues to be little change in the organization of the storm. Dvorak intensity estimates from TAFB and SAB are also unchanged, so the advisory intensity wind speed remains at 45 kt. Carlotta continues to be affected by some northerly shear associated with an upper-level low over the southwestern Gulf of Mexico and no important changes in intensity are anticipated prior to landfall. Carlotta has a small circulation that, after the center crosses the coast, is likely to weaken rapidly over the mountainous terrain of southeastern Mexico and dissipate in a day or so. Animation of the radar images and high-resolution GOES16 visible imagery suggest that the center is inching northward, and the initial motion estimate is 360/1 kt. Carlotta remains in an environment of weak steering currents between mid-level high pressure systems. The track forecast reasoning is that the tropical cyclone will move very slowly northward to north-northwestward, between the two highs. All of the global models show Carlotta moving inland soon. The current official forecast is a little left of the previous one and right of the dynamical model consensus, although some of the input models of this consensus lose the analyzed vortex after 12-24 hours. Regardless of whether the center moves inland, the primary expected hazards from Carlotta continue to be heavy rainfall and the associated risk of life-threatening flash floods and mudslides over the southern parts of Guerrero and Oaxaca. The rainfall threat will be enhanced by moist southwesterly flow over the southern Sierra Madre mountains of Mexico. For details, please see products issued by your local weather office. FORECAST POSITIONS AND MAX WINDS INIT 16/2100Z 16.1N 99.2W 45 KT 50 MPH 12H 17/0600Z 16.7N 99.6W 45 KT 50 MPH 24H 17/1800Z 17.3N 99.9W 35 KT 40 MPH...INLAND 36H 18/0600Z 17.9N 100.1W 20 KT 25 MPH...POST-TROP/INLAND 48H 18/1800Z...DISSIPATED $$ Forecaster Pasch