|
Show Selection: |
| #1155313 (Received by flhurricane at: 10:49 PM 30.Sep.2023) TCDAT2 Tropical Storm Philippe Discussion Number 31 NWS National Hurricane Center Miami FL AL172023 1100 PM AST Sat Sep 30 2023 Philippe`s convective cloud pattern remains rather ragged-looking, but there are very cold cloud tops of -80 deg C or colder over the southeastern part of the circulation. The center of circulation is estimated to be near the northwestern edge of the main area of deep convection. There is little evidence of banding features at this time. The current intensity estimate is kept at 45 kt in agreement with the latest Dvorak classification from TAFB although objective satellite estimates are somewhat lower. A recent scatterometer pass showed slightly higher winds over the southeastern quadrant but these are believed to be rain-inflated. Another Hurricane Hunter aircraft is scheduled to investigate Philippe tomorrow morning to check on the intensity of the storm. The motion is somewhat uncertain since the center is not easy to locate in nighttime satellite imagery. However it appears that Philippe is moving more to the right and the initial motion estimate is now 230/4 kt. Steering currents are expected to remain ill-defined for the next day or two, but a weak mid-level high to the northeast of the system should cause Philippe to turn northwestward on Sunday. In about 3 days, a turn to the north is expected as the cyclone moves along the western side of the high. Late in the forecast period, the system should turn toward the north-northeast on the southeast side of a mid-tropospheric trough over the western Atlantic. The latest track guidance for the next 48 hours or so, in particular the new GFS, has shifted westward from the previous cycle. This has resulted in a westward shift of the model consensus and necessitated a westward shift in the NHC track as well, which is now closer to the northern Leeward Islands. It should be noted that the model guidance continues to show very little outward extent of tropical-storm-force winds over the western semicircle of Philippe through 48 hours, and this forecast still does not necessitate the issuance of tropical storm watches for those islands. However, interests there should continue to monitor the progress of Philippe. Based on the global model forecasts, the system is likely to continue experiencing significant vertical wind shear for the next day or two. Therefore only a slow increase in intensity is forecast during the next couple of days. Later in the forecast period, vertical shear is expected to lessen somewhat which should allow the system to strengthen into a hurricane, as suggested by the regional hurricane model, HAFS-A. However, the official intensity forecast is now above most of the model guidance. FORECAST POSITIONS AND MAX WINDS INIT 01/0300Z 16.1N 57.0W 45 KT 50 MPH 12H 01/1200Z 16.5N 57.7W 45 KT 50 MPH 24H 02/0000Z 17.1N 58.6W 50 KT 60 MPH 36H 02/1200Z 17.8N 59.4W 55 KT 65 MPH 48H 03/0000Z 18.6N 60.3W 60 KT 70 MPH 60H 03/1200Z 19.6N 61.0W 60 KT 70 MPH 72H 04/0000Z 21.1N 61.2W 65 KT 75 MPH 96H 05/0000Z 24.8N 61.1W 75 KT 85 MPH 120H 06/0000Z 28.5N 59.2W 80 KT 90 MPH $$ Forecaster Pasch |
