je.st
news
Tropical Depression Thirteen-E Forecast Discussion Number 1
2017-08-18 16:41:26| National Hurricane Center (East Pacific)
Issued at 800 AM PDT Fri Aug 18 2017 000 WTPZ43 KNHC 181441 TCDEP3 Tropical Depression Thirteen-E Discussion Number 1 NWS National Hurricane Center Miami FL EP132017 800 AM PDT Fri Aug 18 2017 Deep convection associated with the disturbance located over the open eastern Pacific Ocean has become better organized early this morning, and a primary convective band now wraps around the western half of the circulation. Shortwave-IR and first-light visible imagery suggest that a complex, but closed surface circulation exists. NHC is therefore initiating advisories on Tropical Depression Thirteen-E. The initial intensity is set at 30 kt, in agreement with the max winds measured in an earlier ASCAT pass and the latest Dvorak classification from TAFB. Light easterly vertical wind shear has thus far limited convection to the western half of the circulation, but the GFS and ECMWF agree that the shear will lessen as the system moves farther west. Overall, the environment appears conducive for intensification for the next 3 days or so, and the NHC forecast indicates that the cyclone will become a hurricane by the end of this weekend. After that time, the cyclone will begin to weaken over much cooler waters. The NHC forecast is very close to the multi-model consensus, IVCN. Since the center has only recently formed, the initial motion estimate is a fairly uncertain 285/13 kt. There is fairly good agreement among the global models that the tropical cyclone will move generally westward to west-northwestward for the next 72 h along the southern boundary of a mid-level ridge that extends westward well into the eastern Pacific basin. A weakness in the ridge is forecast to develop in about 3 days that should cause the cyclone to slow and turn more toward the northwest and eventually toward the north-northwest. The official forecast is close to a blend of the GFS and ECMWF models. FORECAST POSITIONS AND MAX WINDS INIT 18/1500Z 14.8N 116.5W 30 KT 35 MPH 12H 19/0000Z 15.4N 118.4W 35 KT 40 MPH 24H 19/1200Z 15.9N 121.0W 45 KT 50 MPH 36H 20/0000Z 16.6N 123.6W 55 KT 65 MPH 48H 20/1200Z 17.3N 126.1W 65 KT 75 MPH 72H 21/1200Z 19.1N 130.3W 75 KT 85 MPH 96H 22/1200Z 21.4N 132.4W 65 KT 75 MPH 120H 23/1200Z 23.6N 133.3W 45 KT 50 MPH $$ Forecaster Zelinsky
Tags: number
discussion
tropical
depression
Category:Transportation and Logistics