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| #974471 (Received by flhurricane at: 11:03 PM 12.Jul.2019) TCDAT2 Tropical Storm Barry Discussion Number 11 NWS National Hurricane Center Miami FL AL022019 1000 PM CDT Fri Jul 12 2019 The overall satellite presentation of Barry has improved since this afternoon. The center is located closer to the main convective mass and there has been some expansion of the cirrus outflow. There has also been an increase in the convective banding over the eastern and southeastern portions of the circulation. Both NOAA and Air Force Reserve reconnaissance aircraft have been in the storm this evening. The NOAA aircraft found peak 700 mb flight-level winds of 64 kt in the southeastern quadrant, which still supports an initial intensity of 55 kt. Barry has been able to strengthen over the past day or so despite northerly shear and dry mid-level air. With the recent increase in convection near the center and the expansion of the upper-level outflow, it appears that the shear over the center has decreased. As a result, the NHC intensity forecast calls for Barry to become a hurricane before it reaches the coast of Louisiana. Although this is slightly above the intensity guidance, most of the dynamical models show some modest deepening before landfall. After the center moves inland, steady weakening is expected and the system is predicted to become a remnant low in about 72 hours. Barry has been meandering over the past several hours, but the longer term motion is 300/3 kt. The storm is expected to turn northwestward overnight as a weakness develops in the subtropical ridge that extends over the southeastern United States. This should bring the center of the storm onshore along the south-central coast of Louisiana on Saturday. By Saturday night or early Sunday, Barry is forecast to turn northward around the western portion of the aforementioned ridge. Barry or its remnants should recurve into the mid-latitude westerlies by late Monday. Although the guidance envelope has shifted slightly westward again this cycle, the NHC track is virtually unchanged and is closest to the typically reliable GFS and ECMWF models which lie along the eastern side of the envelope. Key Messages: 1. There is a danger of life-threatening storm surge inundation along the coast of southern and southeastern Louisiana, portions of Lake Pontchartrain, and portions of coastal Mississippi where a Storm Surge Warning is in effect. Water levels have already begun to rise in these areas, with peak inundation expected to occur on Saturday. The highest storm surge inundation is expected between Intracoastal City and Shell Beach. 2. The slow movement of Barry will result in a long duration heavy rainfall and flood threat along the central Gulf Coast, across portions of the Lower Mississippi Valley and north into the Tennessee Valley through the weekend into early next week. Flash flooding and river flooding will become increasingly likely, some of which may be life-threatening, especially across portions of southeast Louisiana into Mississippi. 3. Hurricane conditions are expected along a portion of the coast of Louisiana, where a Hurricane Warning is in effect. Tropical storm conditions are expected elsewhere along much of the Louisiana coast and inland across portions of the lower Mississippi Valley where tropical storm warnings are in effect. FORECAST POSITIONS AND MAX WINDS INIT 13/0300Z 28.6N 91.0W 55 KT 65 MPH 12H 13/1200Z 29.3N 91.5W 65 KT 75 MPH 24H 14/0000Z 30.4N 92.1W 50 KT 60 MPH...INLAND 36H 14/1200Z 31.5N 92.4W 35 KT 40 MPH...INLAND 48H 15/0000Z 32.9N 92.5W 25 KT 30 MPH...INLAND 72H 16/0000Z 35.8N 92.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 17/0000Z 38.7N 90.2W 15 KT 15 MPH...POST-TROP/REMNT LOW 120H 18/0000Z...DISSIPATED $$ Forecaster Brown |