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#1111021 (Received by flhurricane at: 10:48 PM 07.Oct.2022) TCDAT3 Tropical Storm Julia Discussion Number 7 NWS National Hurricane Center Miami FL AL132022 1100 PM EDT Fri Oct 07 2022 Satellite imagery indicates Julia has become somewhat better organized during the past several hours, with the development of a central convective burst with cloud top temperatures colder than -80C and several outer bands appearing. Reports from NOAA and Air Force Reserve Hurricane Hunter aircraft show this has resulted in some strengthening, with the maximum sustained winds near 40 kt and the minimum pressure near 999 mb. However, the aircraft data show that Julia is still disorganized. The 850-mb circulation is weak in the southwestern quadrant, and the 700-mb center is notably south of the 850-mb and surface centers. The surface center is a little to the south of the previous advisory position, possibly due to reformation caused by the convective burst. The initial motion is westward or 270/15 kt. The guidance suggests that a quick westward motion should persist for the next 24-36 h or so as the storm is steered by a strong low- to mid-level ridge to the north. This motion should bring the center near San Andres and Providencia Islands in about 24 h and to the coast of Nicaragua in about 36 h. A slower westward motion is expected after landfall, followed by a turn toward the west-northwest starting at about 48 h. This motion should continue until the system dissipates. The new official track forecast is a little to the south of the previous forecast based mainly on the current initial position, and it lies near the various consensus models. The vertical wind shear over Julia is decreasing, and the environment is becoming favorable for steady to rapid intensification once the cyclone becomes organized enough to take advantage of it. Based on the trend of the intensity guidance and the SHIPS rapid intensification indices, the new intensity forecast calls for Julia to be near hurricane strength when it passes near San Andres and Providencia, and for it to reach a peak intensity of 70 kt at landfall in Nicaragua. After landfall, the cyclone is expected to rapidly weaken over the rugged terrain of Central America, with the surface center dissipating between 72-96 h. Although Julia is expected to dissipate over Central America by Monday night, various model solutions depict Julia`s leftover vorticity moving over the eastern Pacific waters, over the Bay of Campeche, or both after that time. However, it is still unclear at this time if that will lead to genesis of a new tropical cyclone. We`ll continue to monitor model trends and update the forecast as needed. Regardless of new development, the set up is likely to lead to heavy rains over Central America for several days, which could cause life-threatening flash floods and mudslides, especially in areas of mountainous terrain. Key Messages: 1. Julia is forecast to strengthen into a hurricane by Saturday evening or Saturday night while it moves over the southwestern Caribbean Sea, and a Hurricane Warning is in effect for portions of the Nicaragua coast and the offshore Colombian islands. Hurricane-force winds and a dangerous storm surge are expected in areas where the core of the system crosses the islands and moves onshore in Nicaragua. 2. Life-threatening flash flooding and mudslides are expected across portions of Central America this weekend. FORECAST POSITIONS AND MAX WINDS INIT 08/0300Z 12.8N 76.1W 40 KT 45 MPH 12H 08/1200Z 12.8N 78.7W 50 KT 60 MPH 24H 09/0000Z 12.7N 81.5W 60 KT 70 MPH 36H 09/1200Z 12.8N 83.7W 70 KT 80 MPH...INLAND 48H 10/0000Z 13.1N 86.1W 45 KT 50 MPH...INLAND 60H 10/1200Z 13.6N 88.5W 30 KT 35 MPH...INLAND 72H 11/0000Z 14.4N 90.9W 25 KT 30 MPH...POST-TROP/INLAND 96H 12/0000Z...DISSIPATED $$ Forecaster Beven |