ZCZC HFOTCDCP5 ALL TTAA00 PHFO DDHHMM TROPICAL STORM MADELINE DISCUSSION NUMBER 26 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP142016 1100 AM HST THU SEP 01 2016 Bursts of deep convection associated with Madeline have continued over the past several hours. Although obscured by the cirrus shield, an SSMIS pass at 1437 UTC and ASCAT NRCS data from last night have indicated that the low level center is embedded within the southwestern side of the deep convection. Subjective Dvorak fixes came in at 3.0/45 kt from PHFO and JTWC, and 2.5/35 kt from SAB. CIMSS ADT indicated 33 kt and CIMSS SATCON showed 42 kt. Using a blend of these estimates, the initial intensity for this advisory has been lowered to 40 kt. It should be noted that last night's ASCAT pass showed all values at less than 35 kt though deep convection was less active during the time of the pass. The initial motion for this advisory is 260/11 kt. Madeline appears to have turned more toward the west as previously forecast due to steering by a low- to mid-level ridge centered to the north and northwest of the cyclone. Most of the dynamical objective aids are tightly clustered around a westward track over the next 2 to 3 days, with the GFDL a notable northern outlier. The forecast is largely an update of the previous forecast, which places the center of Madeline near Johnston Island on Saturday. The main factor influencing the intensity of Madeline over the next several days will be the amount of vertical wind shear that will affect the system since sea surface temperatures and the oceanic heat content are more than adequate to support a stronger cyclone. An upper level trough currently northeast of the main Hawaiian Islands is projected by the global models to move generally westward over the next 2 to 3 days. This trough is expected to produce moderate to strong vertical wind shear on Madeline which should significantly weaken Madeline. SHIP and LGEM show slow weakening followed by slight strengthening late in the forecast period. The GFS, ECMWF, and HWRF indicate a faster weakening with the ECMWF dissipating Madeline within 48 hours. The forecast is more in line with the dynamical models, and is close to the previous forecast. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 16.5N 157.6W 40 KT 45 MPH 12H 02/0600Z 16.5N 159.5W 40 KT 45 MPH 24H 02/1800Z 16.3N 162.1W 35 KT 40 MPH 36H 03/0600Z 16.3N 164.8W 30 KT 35 MPH 48H 03/1800Z 16.4N 167.3W 25 KT 30 MPH 72H 04/1800Z 17.2N 171.3W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 05/1800Z 18.2N 175.1W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 06/1800Z...DISSIPATED $$ Forecaster Kodama NNNN