WDPN33 PGTW 232100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 19W (NINETEEN) WARNING NR 006// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 14.0N 136.5E INITIAL INTENSITY: 30 KTS GEOGRAPHIC REFERENCE: 286 NM NORTH-NORTHWEST OF YAP MOVEMENT PAST 6 HOURS: NORTHWARD AT 04 KTS SIGNIFICANT WAVE HEIGHT: 12 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED SHORTWAVE INFRARED (SWIR) SATELLITE IMAGERY DEPICTS A COMPACT AND FULLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC). DEEP CONVECTION HAS REMAINED DISPLACED WEST OF THE LLCC OVERNIGHT DUE TO PERSISTENT MODERATE TO HIGH NORTHEASTERLY SHEAR. A 231633Z AMSR2 COLOR-ENHANCED 89GHZ IMAGE REVEALED THE EXPOSED LLCC EAST OF A SMALL POCKET OF DEEP CONVECTION WITH AN EMBEDDED MID-LEVEL MESOVORTEX. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON THE EXPOSED LLCC IN THE SWIR. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON A BLEND OF THE OBJECTIVE AND SUBJECTIVE INTENSITY ESTIMATES NOTED BELOW. ENVIRONMENTAL CONDITIONS ARE ASSESSED AS UNFAVORABLE, WITH MODERATE TO HIGH NORTHEASTERLY VERTICAL WIND SHEAR AND DRY MID-LEVEL AIR ALONG THE EASTERN FLANK OFFSETTING THE OTHERWISE FAVORABLE OCEANIC CONDITIONS AND SUPPORTIVE UPPER-LEVEL OUTFLOW. INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND RADII). CURRENT STEERING MECHANISM: NORTHWESTERN FLANK OF A LOW- TO MID-LEVEL NEAR EQUATORIAL RIDGE (NER) TO THE SOUTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.5 - 35 KTS RJTD: T1.5 - 25 KTS KNES: T2.5 - 35 KTS CIMSS SATCON: 35 KTS AT 231840Z CIMSS ADT: 33 KTS AT 231800Z CIMSS AIDT: 32 KTS AT 231800Z CIMSS D-MINT: 27 KTS AT 231648Z CIMSS D-PRINT: 29 KTS AT 231800Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE VWS: 20-25 KTS SST: 29-30 CELSIUS OUTFLOW: MODERATE EQUATORWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: NOT APPLICABLE 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TROPICAL DEPRESSION (TD) 19W (NINETEEN) HAS TAKEN A BIT OF A SLOW NORTHWARD JOG OVER THE PAST SIX HOURS, LIKELY DUE TO AN ABORTED ATTEMPT AT VORTEX ALIGNMENT WITH THE MID-LEVEL MESOVORTEX EMBEDDED IN THE CONVECTION TO THE WEST. SINCE THE 1800Z ANALYSIS, THE EXPOSED LLCC APPEARS TO HAVE RESUMED A NORTHEASTWARD TRACK INTO THE CLEAR, RELATIVELY DRY AIR EAST OF THE CONVECTION WHICH CONTINUES TO SLIDE WESTWARD UNDER THE MODERATE SHEAR CONDITIONS. NOW HAVING RESUMED COURSE, THE SYSTEM IS FORECAST TO CONTINUE TRACK IN A GRACEFUL ARC, TURNING NORTHWARD BY TAU 12 AS IT REACHES THE NORTHERN EDGE OF THE NER AND THE STEERING IS PICKED UP BY THE STR FAR TO THE NORTHEAST. BY TAU 36, THE SYSTEM TURNS NORTHWESTWARD, FOLLOWING IN THE WAKE OF TY 17W AS IT BEGINS BINARY INTERACTION WITH 17W. REGARDING INTENSITY, THE SYSTEM IS HIGHLY UNLIKELY TO BE ABLE TO INTENSIFY IN THE FACE OF PERSISTENT SHEAR, WHICH IS ONLY EXPECTED TO INCREASE. FURTHER INFLUXES OF DRY AIR WILL ADD INSULT TO INJURY AND TD 19W WILL CONTINUE TO WEAKEN THROUGH THE FORECAST PERIOD BEFORE DISSIPATING NO LATER THAN TAU 48. MODEL DISCUSSION: TRACK GUIDANCE IS IN GOOD AGREEMENT WITH MINIMAL CROSS-TRACK SPREAD THROUGH THE FORECAST PERIOD. DISCOUNTING THE UKMET ENSEMBLE MEAN WHICH TURNS THE SYSTEM WEST AT TAU 24, ALONG-TRACK SPREAD INCREASES TO 225NM, BETWEEN THE FAST GFS AND THE SLOW NAVGEM, BY TAU 48. THE JTWC FORECAST IS PLACED NEAR THE CONSENSUS MEAN AND THE EXPERIMENTAL GOOGLE DEEPMIND TRACKER WITH HIGH CONFIDENCE. INTENSITY GUIDANCE IS ALSO IN GOOD AGREEMENT THAT THE SYSTEM WILL STEADILY WEAKEN THROUGH DISSIPATION BETWEEN TAU 24 AND TAU 48. THE ONLY EXCEPTION IS CTCX, WHICH DEPICTS A REINTENSIFICATION AFTER TAU 24. FORECAST CONFIDENCE: TRACK 00-72 HR: HIGH INTENSITY 00-72 HR: MEDIUM// NNNN