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#931796 (Received by flhurricane at: 4:42 PM 06.Jul.2018) TCDAT2 Hurricane Beryl Discussion Number 6 NWS National Hurricane Center Miami FL AL022018 500 PM AST Fri Jul 06 2018 Beryl has lost its tiny pinhole eye from earlier this morning, but the system continues to produce a compact area of deep convection near the center. Since Dvorak estimates have changed little from six hours ago, the initial intensity will remain 70 kt for this advisory. Global model fields continue to show an upper-level anticyclone moving westward in tandem with the hurricane for the next 48 hours or so, which would keep the vertical shear low enough to allow for some intensification. After 48 hours, however, the upper-level pattern is expected to evolve to southerlies or westerlies over the system, which would increase the shear and cause weakening. Given the seemingly favorable environment for the next 2 days, the NHC intensity forecast continues to lie along the upper bound of the guidance. After 48 hours, the intensity forecast is closer to the HCCA model and the intensity consensus. It bears repeating that the intensity forecast remains highly uncertain given Beryl`s small size, and the cyclone could just as easily dissipate into an open wave sooner than indicated in the official forecast. The hurricane is moving westward, or 270/13 kt, and may have actually lost a little latitude today. Given the more southerly initial position, the track guidance suite has shifted south accordingly, and the new NHC track has been adjusted in that direction as well, lying between the model consensus aids and the southern edge of the solutions. Additional southward adjustments to the forecast track are likely if Beryl does not gain latitude soon. Given the larger-than-normal uncertainties associated with Beryl`s future track and intensity, the governments and meteorological services of several of the countries in the Lesser Antilles have elected to issue tropical storm or hurricane watches for their islands, sooner than the typical 48-hour threshold for the onset of tropical-storm-force winds. Please refer to products issued by the meteorological services of those respective countries for additional information. Due to a technical issue, the wind speed probability values at land locations in the wind speed probability text product are too high and do not reflect reduced probabilities that are expected over land. The wind speed probability values provided in the graphics on the NHC website at hurricanes.gov, and in the publicly disseminated grid files do correctly reflect the reduced probabilities over land. As a result, users should refer to the NHC website graphics and gridded products instead of the text product for the most accurate wind speed probability values until this problem is resolved. Key Messages: 1. Beryl is expected to be a hurricane when it moves through the Lesser Antilles Sunday night or Monday, and the chance of some islands receiving direct impacts from wind and rainfall are increasing. Hurricane and tropical storm watches have been issued by some of the countries in the Lesser Antilles, and additional watches could be required for other islands tonight or early Saturday. 2. Due to its very small size, there is greater-than-usual uncertainty in the analysis of Beryl`s current intensity, and confidence in the official intensity forecast is also lower than normal. Rapid changes in intensity, both up and down, that are difficult to predict are possible during the next couple of days. FORECAST POSITIONS AND MAX WINDS INIT 06/2100Z 10.6N 47.8W 70 KT 80 MPH 12H 07/0600Z 11.1N 49.4W 75 KT 85 MPH 24H 07/1800Z 11.9N 51.8W 80 KT 90 MPH 36H 08/0600Z 12.9N 54.7W 80 KT 90 MPH 48H 08/1800Z 13.8N 58.2W 80 KT 90 MPH 72H 09/1800Z 16.1N 66.7W 55 KT 65 MPH 96H 10/1800Z 18.5N 75.0W 40 KT 45 MPH 120H 11/1800Z...DISSIPATED $$ Forecaster Berg |