Official Discussion issued by the National Hurricane Center
(AL052024) DATA RELEASED: 8/11/2024 9:00:00 PM UTC
Copy of official data Potential Tropical Cyclone Five Discussion Number 1 NWS National Hurricane Center Miami FL AL052024 500 PM AST Sun Aug 11 2024 NHC has been monitoring the a broad area of low pressure associated with a tropical wave over the tropical Atlantic during the past several days. Satellite images and earlier ASCAT data indicate that the low has a broad circulation, but there is no evidence of a well-defined center yet. The associated shower and thunderstorm activity is showing some signs of organization, but visible satellite imagery suggests that dry air is entraining into the circulation. However, since the disturbance is forecast to become a tropical storm in the next day or so, and there is a risk of tropical-storm-force winds across portions of the Leeward Islands during that time, advisories are being initiated on Potential Tropical Cyclone Five. The NOAA and Air Force Hurricane Hunters will be investigating this system on Monday. The estimated motion of Potential Tropical Cyclone Five is 285/18-kt. The track guidance is in fairly good agreement on a fast west-northwestward motion through the next 36-48 h. This motion should bring the system near or over the Leeward Islands on Tuesday. Thereafter, a deep-layer trough moving off the U.S. East Coast should approach this system, inducing a turn to the northwest by Wednesday and to the north thereafter. This should bring the system in the general vicinity of the Virgin Islands and Puerto Rico Tuesday night, then emerging into the Atlantic north of Puerto Rico on Wednesday. The NHC track forecast is based on a blend of the latest GFS and ECMWF models. Users should keep in mind that the track forecasts for potential tropical cyclones are inherently more uncertain than normal since the system lacks a wellG��defined center. Potential Tropical Cyclone Five is currently located in an environment of moderate easterly vertical wind shear. Over the next day or two, the wind shear is forecast to decrease some while the disturbance moves into an increasingly unstable environment. Given the current organizational state of the convection and low-level wind structure, the system likely needs at least one more day before it can organize into a tropical cyclone. Around the time the system reaches the Leeward Islands, it will be moving into an increasingly conducive environment for strengthening. Therefore, once the system is able to develop an inner core it should have an opportunity to strengthen at a faster rate. The favorable environment will likely continue in the 3 to 5-day time frame, and this system is forecast to be a strengthening hurricane when it is moving northward over the western Atlantic. The NHC intensity forecast is slightly below the intensity consensus in the short term, but falls in line with the consensus aids beyond a couple of days. Key Messages: 1. The disturbance is expected to become a tropical storm before reaching the Leeward Islands, where Tropical Storm Watches are in effect. Tropical storm conditions could begin on Tuesday for portions of the area. 2. Heavy rainfall may result in locally considerable flash flooding and mudslides in portions of the northern Leeward Islands Tuesday and Wednesday, and into Puerto Rico Wednesday through Thursday. 3. Additional watches or warnings will likely be required for the British and U.S. Virgin Islands, and Puerto Rico tonight or early Monday, and interests in these locations should monitor the progress of this system. FORECAST POSITIONS AND MAX WINDS INIT 11/2100Z 13.6N 48.0W 25 KT 30 MPH...POTENTIAL TROP CYCLONE 12H 12/0600Z 14.3N 51.2W 30 KT 35 MPH...POTENTIAL TROP CYCLONE 24H 12/1800Z 15.2N 55.5W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 36H 13/0600Z 15.9N 59.2W 40 KT 45 MPH...TROPICAL CYCLONE 48H 13/1800Z 17.0N 62.2W 45 KT 50 MPH 60H 14/0600Z 18.3N 64.4W 55 KT 65 MPH 72H 14/1800Z 19.8N 66.1W 65 KT 75 MPH 96H 15/1800Z 23.9N 67.4W 85 KT 100 MPH 120H 16/1800Z 27.7N 66.3W 95 KT 110 MPH $$ Forecaster Hagen/Cangialosi |