Issued at 500 AM AST Fri Jun 23 2023
000 WTNT43 KNHC 230903 TCDAT3 Tropical Storm Bret Discussion Number 16...Updated NWS National Hurricane Center Miami FL AL032023 500 AM AST Fri Jun 23 2023 Updated to include discontinuation of the Tropical Storm Warning for Dominica. Bret's center is now over the southeastern Caribbean Sea, but convective activity extends more than 300 n mi to the east across the Windward Islands and adjacent Atlantic waters. An Air Force Reserve Hurricane Hunter aircraft measured peak 850-mb flight-level winds of 60 kt and SFMR winds of 49 kt to the north of the center on its last pass before heading back to base, and the initial intensity is therefore maintained at 50 kt. The plane had found that Bret's central pressure had dropped again, back down to 1001 mb. Bret continues to move quickly westward, or 270/16 kt, to the south of an area of high pressure located over the western Atlantic. The subtropical ridge is expected to continue steering Bret quickly westward across the eastern and central Caribbean Sea during the next couple of days. There are no changes to the track model guidance, or the track forecast reasoning, and the official NHC forecast is a little faster than the model consensus aids, hedging toward the GFS and ECMWF solutions. Bret is approaching an upper-level trough located over the eastern Caribbean Sea, and the resulting deep-layer shear over the storm is analyzed to be about 25 kt out of the west-southwest. Even stronger shear and a dry mid-level environment are expected to cause Bret to gradually weaken during the next couple of days, with global model fields showing the system degenerating into a trough over the central Caribbean Sea some time over the weekend. The NHC forecast shows dissipation by Sunday, but some model fields suggest it could happen earlier than that. KEY MESSAGES: 1. Bret is moving westward over the southeastern Caribbean Sea, but trailing rainbands with embedded gusty winds continue to affect portions of the Windward Islands. These conditions should gradually subside through the day. 2. A Tropical Storm Warning remains in effect for St. Vincent and the Grenadines, St. Lucia, and Martinique. FORECAST POSITIONS AND MAX WINDS INIT 23/0900Z 13.4N 62.9W 50 KT 60 MPH 12H 23/1800Z 13.6N 65.2W 45 KT 50 MPH 24H 24/0600Z 13.8N 68.6W 40 KT 45 MPH 36H 24/1800Z 13.9N 72.1W 35 KT 40 MPH 48H 25/0600Z 13.9N 75.6W 30 KT 35 MPH 60H 25/1800Z...DISSIPATED $$ Forecaster Berg