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#903749 (Received by flhurricane at: 11:08 AM 19.Sep.2017) TCDAT2 Hurricane Jose Discussion Number 57 NWS National Hurricane Center Miami FL AL122017 1100 AM EDT Tue Sep 19 2017 Satellite imagery and reports from an Air Force Reserve Hurricane Hunter aircraft indicate that Jose`s overall structure and wind field have changed little since the previous advisory. Although the highest 700-mb flight-level wind and SFMR surface winds reported by the aircraft were 66 kt and 57 kt, respectively, these winds were observed in areas of little or no convection. Given the large size of Jose`s wind field, it unlikely that the aircraft sampled the strongest winds, and the initial intensity is held at 65 kt. The aircraft also measured a central pressure of 976 mb, indicating that Jose remains a strong cyclone. The low-level center has been wobbling around inside the larger inner-core circulation, resulting in a forward motion a little west of due north or 350/06 kt. Overall there is no significant change to the previous track forecast. The global and regional models remain in good agreement on Jose slowing down and turning toward the northeast and east over the next couple days as it moves around a ridge over the western Atlantic. On days 3-5, the models agree on a high-latitude ridge building to the north of the cyclone, forcing Jose to move slowly or drift southward over the North Atlantic. The official forecast track is similar to the previous advisory, and lies close to a blend of the various consensus models. Since the previous advisory, shallow convection has been increasing in both depth and areal coverage in the southeastern semicircle, while deeper convection has remained over the northwestern semicircle. The recent formation of convection to the southeast is beginning to give Jose the appearance of developing a large truck-tire eye with a diameter of approximately 100 nmi. Such eye patterns typically indicate a fairly stable cyclone that doesn`t weaken or weakens only slowly. Although the center of Jose will be moving over 21C SSTs by 36-48 h, a significant portion of the large circulation will still be situated over water south of the Gulf Stream that is positioned along 40N latitude, which will maintain a southerly feed of warm, moist, unstable air into and north of the center. Given the combination of the aforementioned favorable thermodynamic conditions and only modest vertical wind shear of 15-20 kt, the intensity forecast remains basically unchanged from the previous advisory, and is close to a blend of the IVCN and HCCA consensus models. KEY MESSAGES: 1. While the center of Jose is forecast to remain offshore of the U.S. coast, the large cyclone is expected to cause some direct impacts in portions of New England, and a tropical storm warning is in effect for the coast of Rhode Island and a part of the Massachusetts coast, including Cape Cod. Any deviation to the left of the NHC forecast track would increase the likelihood and magnitude of impacts along the U.S. east coast from Long Island to southern New England. 2. Minor to moderate coastal flooding is possible from Delaware to southern New England during the next several days. Please see products issued by local National Weather Service forecast offices. 3. Swells generated by Jose are affecting Bermuda, the Bahamas, and much of the U.S. east coast. These swells are likely to cause dangerous surf and rip current conditions for the next several days in these areas. 4. Jose will produce heavy rain over a small part of southern New England and eastern Long Island as it passes offshore of these locations on Tuesday and Wednesday. Total accumulations of 1 to 3 inches are expected over eastern Long Island, southeast Connecticut, southern Rhode Island, and southeast Massachusetts. 3 to 5 inches are expected for Martha`s Vineyard, Nantucket, and Cape Cod. This rainfall could cause isolated flooding. FORECAST POSITIONS AND MAX WINDS INIT 19/1500Z 36.5N 71.7W 65 KT 75 MPH 12H 20/0000Z 37.8N 70.9W 65 KT 75 MPH 24H 20/1200Z 39.1N 69.7W 60 KT 70 MPH 36H 21/0000Z 39.9N 68.1W 55 KT 65 MPH 48H 21/1200Z 39.9N 67.1W 50 KT 60 MPH 72H 22/1200Z 39.2N 66.9W 45 KT 50 MPH...POST-TROPICAL 96H 23/1200Z 38.7N 67.2W 40 KT 45 MPH...POST-TROPICAL 120H 24/1200Z 38.4N 67.7W 40 KT 45 MPH...POST-TROPICAL $$ Forecaster Stewart |