Mid-level dry air entrainment preventing significant intensification of TC 01S(PADDY), 23/09utc

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON TC 01S(PADDY).

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 01S IS FORECAST TO MEANDER SLOWLY WESTWARD ALONG THE NORTHERN PERIPHERY OF THE LOW- TO MID-LEVEL SUBTROPICAL RIDGE(STR) THROUGH THE FORECAST PERIOD. THE SYSTEM HAS STRUGGLED TO CONSOLIDATE DUE, LARGELY, TO THE PRESENCE OF SIGNIFICANT MID-LEVEL DRY AIR BUT HAS MAINTAINED WEAK BANDING OVER THE SOUTHERN SEMICIRCLE. TC 01S SHOULD CONTINUE TO STEADILY WEAKEN DUE TO DRY AIR ENTRAINMENT AS WELL AS WEAK OUTFLOW ALOFT, AND SHOULD DISSIPATE BY 48H.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS PERSISTENT DEEP CONVECTION OVER A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION (LLC). A 230627Z AMSR2 89GHZ COLOR COMPOSITE MICROWAVE IMAGE INDICATES SHALLOW BANDING WRAPPING INTO A BROAD CENTER POSITIONED ON THE NORTHERN EDGE OF A CURVED CONVECTIVE BAND, THEREFORE, THERE IS MEDIUM CONFIDENCE IN THE INITIAL POSITION. THE INITIAL INTENSITY REMAINS ASSESSED AT 40 KNOTS AND IS HEDGED ABOVE THE PGTW AND APRF DVORAK CURRENT INTENSITY ESTIMATES BASED ON THE CIMSS ADT ESTIMATE. ENVIRONMENTAL CONDITIONS REMAIN MARGINALLY FAVORABLE WITH ROBUST POLEWARD OUTFLOW AND LOW VERTICAL WIND SHEAR OFFSET BY MID-LEVEL DRY AIR ENTRAINMENT. SEA SURFACE TEMPERATURES ARE CONDUCIVE AT 26-27C.

MODEL DISCUSSION: EXCLUDING NAVGEM, WHICH IS TRACKING THE SYSTEM SOUTHWESTWARD INTO A STRONG STR, AND THE GFS ENSEMBLE MEAN (NORTHERN OUTLIER), THE BULK OF THE NUMERICAL MODEL GUIDANCE REMAINS IN FAIR AGREEMENT LENDING MEDIUM CONFIDENCE TO THE JTWC FORECAST TRACK. INTENSITY GUIDANCE SUPPORTS THE STEADY WEAKENING TREND LEADING TO DISSIPATION WITH HWRF AND COAMPS-TC INDICATING DISSIPATION PRIOR TO 48H.

230627Z AMSR2 89GHZ COLOR COMPOSITE MICROWAVE IMAGE INDICATES SHALLOW BANDING WRAPPING INTO A BROAD CENTER POSITIONED ON THE NORTHERN EDGE OF A CURVED CONVECTIVE BAND