000 WTPA41 PHFO 152036 TCDCP1 Tropical Storm Darby Discussion Number 26 NWS Central Pacific Hurricane Center Honolulu HI EP052022 1100 AM HST Fri Jul 15 2022 Darby lost its deep convection around 1400Z, as a result of persistent shear of 25 to 30 kt, per the UW-CIMSS deep shear analysis. The loss of deep convection has left behind an exposed low level center. Dvorak intensities from PHFO and PGTW were 55 kt, SAB at 45 kt and UW-CIMSS ADT at 35 kt. The CIMSS SATCON from 1638Z had a CI of 49 kt. With the convection gone, and a high confidence in the downward trend, have opted to go with a conservative blend of these intensities for an initial value of 50 kt. The initial motion is 275/13. With the convection sheared off, but cloud tops still reaching near 20K feet, the mid levels are helping to guide Darby. Over the next day or so, the low-level flow will become the steering force for the system. Both the mid- and low-levels are dominated by a large anticyclone far to the north of the cyclone, which will maintain a westerly track. The track guidance has become a little less tightly clustered as it has been over the last several runs, with some variations in how the models are handling the rate of weakening. The current forecast track remains close to the past track, near the center of the guidance envelope. The forecast track keeps Darby in a moderately sheared environment for the next couple of days, and continuing along the 25-26C sea surface temperatures (SST). The shear, SST and climatologically low mid-level relative humidity values near the track all work against redevelopment of Darby. The intensity forecast has been lowered some from the past forecast, to be in line with the latest guidance consensus, which leads to dissipation of the remnant circulation by Sunday night. FORECAST POSITIONS AND MAX WINDS INIT 15/2100Z 17.6N 147.7W 50 KT 60 MPH 12H 16/0600Z 17.6N 150.2W 40 KT 45 MPH 24H 16/1800Z 17.5N 153.9W 35 KT 40 MPH 36H 17/0600Z 17.2N 157.7W 30 KT 35 MPH 48H 17/1800Z 16.9N 161.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 60H 18/0600Z...DISSIPATED $$ Forecaster M Ballard/R Ballard