ZCZC MIATCDEP2 ALL TTAA00 KNHC DDHHMM Hurricane Barbara Discussion Number 8 NWS National Hurricane Center Miami FL EP022019 1100 PM HST Mon Jul 01 2019 Recent METOP-A and -B microwave images indicate that Barbara's eyewall is no longer broken and has been able to shield itself from the dry air that had been penetrating the inner core. An eye is also becoming more apparent in infrared satellite imagery. Subjective Dvorak estimate have increased to T5.0/90 kt from TAFB and T5.5/102 kt from SAB, while objective numbers are T5.5/102 kt and 81 kt from UW-CIMSS ADT and SATCON, respectively. Barbara's initial intensity is therefore set at 95 kt, meaning that the rapid intensification phase continues. Low vertical shear, beneficial upper-level outflow, and deep warm water are likely to foster additional strengthening for the next 24-36 hours, with Barbara expected to become a major hurricane soon. Oceanic heat content values decrease markedly by 36 hours, which should lead to gradual weakening, followed by faster weakening on days 4 and 5 when southwesterly shear increases. The updated NHC intensity forecast is not too dissimilar from the previous forecast during the first day or two and still shows Barbara's peak intensity reaching category 4 intensity during that period. The models are in good agreement that environmental conditions will become quite hostile after day 3, and the new forecast shows a faster weakening rate toward the end of the forecast period. In fact, if the GFS and European models are correct, Barbara could lose its deep convection and become a post-tropical cyclone over the weekend. Barbara's trajectory remains westward at 280/13 kt, with steering dominated by a subtropical ridge which extends westward from northern Mexico. The hurricane is expected to gradually reach the western periphery of the ridge in the coming days, which should cause it to turn northwestward and slow down by 48-72 hours. After that time, a weaker Barbara should turn back toward the west and accelerate, steered by lower-level trade winds. Negligible adjustments, primarily after 48 hours, were made to the NHC official track forecast, which lies close to the TVDG multi-model consensus. NOTE: Beginning this hurricane season, all National Hurricane Center eastern Pacific advisory products that utilize local time, and the corresponding graphical products, will use Hawaiian Standard Time (HST) instead of Pacific Daylight Time (PDT) or Standard Time (PST) if the final forecast point is west of 140W. Since Barbara's day 5 official forecast point is now west of 140W, advisory products are now being issued in Hawaiian Standard Time. FORECAST POSITIONS AND MAX WINDS INIT 02/0900Z 12.0N 121.1W 95 KT 110 MPH 12H 02/1800Z 12.4N 122.9W 105 KT 120 MPH 24H 03/0600Z 13.0N 125.0W 115 KT 130 MPH 36H 03/1800Z 13.8N 126.9W 120 KT 140 MPH 48H 04/0600Z 14.7N 128.6W 110 KT 125 MPH 72H 05/0600Z 16.9N 132.0W 80 KT 90 MPH 96H 06/0600Z 18.5N 136.0W 55 KT 65 MPH 120H 07/0600Z 19.0N 141.5W 40 KT 45 MPH $$ Forecaster Berg NNNN