ZCZC MIATCDEP4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM ULIKA DISCUSSION NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL EP192016 800 AM PDT WED SEP 28 2016 Ulika was maintaining a small central dense overcast (CDO), with the center well embedded within this convective mass overnight. Since then, the cloud pattern has undergone considerable degradation. The CDO has become much less distinct, to the point that it has no longer become discernible. The deep convection in the former CDO has also decreased in coverage and cloud top temperatures have warmed substantially. TAFB and SAB provided a satellite classifications of T4.0 and T2.5 at 1200 UTC, respectively. Since that time, the cyclone's cloud pattern has further degraded, and the initial intensity is lowered to a possibly generous 60 kt. Ulika's environment already appears to have become much less favorable. West-southwesterly to southwesterly shear is only likely to increase as the cyclone gains latitude during the next couple of days. In fact, the SHIPS model output indicates more than 30 kt of shear by 36 hours. This, combined with a marginally moist environment and an increasingly convergent flow aloft, means that steady weakening is most likely. Global models show Ulika being sheared apart in about 2 days, with the mid-level center racing northeastward away from the low-level center. Rapid weakening should occur by then, if it has not begun already, and remnant low status is forecast in 72 hours. The new intensity forecast is lowered relative to the previous one, and is near or below the multi-model consensus. The initial motion is 030/06. Ulika should turn northward soon, as it rotates around a nearly stationary mid-tropospheric low seen in water vapor imagery around 17N 143W. Once the system decouples fully, the shallower cyclone's motion will be governed by the low-level trade wind flow and turn westward with an increase in forward speed. The new track forecast is a little to the right of the previous one through 24 hours and then is very similar, with the new forecast close to the multi-model consensus. FORECAST POSITIONS AND MAX WINDS INIT 28/1500Z 14.5N 138.7W 60 KT 70 MPH 12H 29/0000Z 15.3N 138.6W 55 KT 65 MPH 24H 29/1200Z 16.0N 139.2W 50 KT 60 MPH 36H 30/0000Z 16.7N 140.1W 45 KT 50 MPH 48H 30/1200Z 17.3N 141.2W 35 KT 40 MPH 72H 01/1200Z 17.5N 144.1W 30 KT 35 MPH...POST-TROP/REMNT LOW 96H 02/1200Z 17.5N 148.6W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 03/1200Z...DISSIPATED $$ Forecaster Kimberlain NNNN
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