Show Selection: |
#982968 (Received by flhurricane at: 4:57 AM 19.Sep.2019) TCDAT5 Tropical Storm Jerry Discussion Number 8 NWS National Hurricane Center Miami FL AL102019 500 AM AST Thu Sep 19 2019 A fortuitous 0531 UTC AMSR2 microwave overpass indicated that Jerry`s inner core has significantly become better organized this morning. The image revealed a nearly enclosed banding eye feature with the curved band wrapping around the east portion of the cyclone. Based on the much improved cloud pattern and a blend of the subjective and objective satellite intensity estimates, the initial intensity is increased to 60 kt for this advisory. Jerry is expected to strengthen further in the short term and become a hurricane later today. Afterward, the statistical-dynamical intensity models show some moderate northwesterly shear impinging on the northern half of the cyclone, which should arrest the early period intensification. Beyond the 48 hour period, a majority of the large-scale models indicate increasing westerly vertical shear as Jerry moves northwest of an upper anti-cyclone situated to the north of Hispaniola. Therefore, a weakening trend is expected through the remaining portion of the forecast. The NHC forecast is slightly below the previous advisory after the 48 hour period, but above the HFIP HCCA and IVCN consensus models, and as well as the HWRF. The initial motion is estimated to be west-northwestward, or 290/14 kt. There are no significant changes to the forecast track philosophy. The cyclone is forecast to be steered by the southeasterly flow generated by a subtropical ridge to the northeast of Jerry through the 48 hour period. Around day 3, Jerry is likely to turn northwest to north-northwest, in response to a growing weakness in the aforementioned mid-tropospheric ridge along 70-75W longitude. The official track forecast is based on a blend of the various consensus aids. Key Messages: 1. Jerry is expected to become a hurricane before it moves close to the northern Leeward Islands Friday. Although the core of Jerry is currently expected to pass north of the islands, tropical-storm- force winds and locally heavy rainfall are possible, and tropical storm watches have been issued for a portion of this area. FORECAST POSITIONS AND MAX WINDS INIT 19/0900Z 16.0N 53.2W 60 KT 70 MPH 12H 19/1800Z 16.8N 55.2W 70 KT 80 MPH 24H 20/0600Z 17.8N 57.9W 70 KT 80 MPH 36H 20/1800Z 18.9N 60.9W 65 KT 75 MPH 48H 21/0600Z 20.1N 63.7W 65 KT 75 MPH 72H 22/0600Z 22.9N 68.2W 60 KT 70 MPH 96H 23/0600Z 26.0N 70.0W 65 KT 75 MPH 120H 24/0600Z 29.5N 68.5W 65 KT 75 MPH $$ Forecaster Roberts |