ZCZC HFOTCDCP3 ALL TTAA00 PHFO DDHHMM Tropical Depression Miriam Discussion Number 30 NWS Central Pacific Hurricane Center Honolulu HI EP152018 500 AM HST Sun Sep 02 2018 The center of Miriam has been completely devoid of deep convection for almost 24 hours as nearly 50 kt of southwesterly vertical wind shear has taken its toll on the system. The latest subjective Dvorak current intensity estimates range from unclassifiable by SAB to T1.5/25 kt by JTWC, and T2.0/30 kt by PHFO. The most recent UW-CIMSS ADT yielded an estimated intensity of 25 kt. Based on a blend of these estimates, the initial intensity is lowered to 30 kt for this advisory. The initial motion is 320 deg / 12 kt. A broad mid- to upper-level trough to the northwest of Miriam will maintain the very strong vertical wind shear during the next couple of days. Since Miriam has transitioned to a shallow low-level cloud swirl, it is now being steered more toward the northwest under the influence of a deep subtropical ridge located to the northeast. This northwestward motion will likely persist through Monday. The latest forecast track is close to the previous advisory, and remains near the middle of the guidance envelope and close to the consensus model guidance, TVCE and HCCA. Under the hostile vertical wind shear and decreasing SSTs, Miriam will continue weakening. The latest intensity forecast weakens Miriam at a slightly slower rate than almost all of the guidance, and is closest to the GFS output. Note that Miriam is forecast to become a remnant low later today, followed by dissipation late Monday. FORECAST POSITIONS AND MAX WINDS INIT 02/1500Z 26.1N 143.9W 30 KT 35 MPH 12H 03/0000Z 27.3N 145.3W 25 KT 30 MPH...POST-TROP/REMNT LOW 24H 03/1200Z 28.6N 147.4W 25 KT 30 MPH...POST-TROP/REMNT LOW 36H 04/0000Z 29.7N 149.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 48H 04/1200Z...DISSIPATED $$ Forecaster Houston NNNN