MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 27W (MA-ON) WARNING NR 03// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION (TD) 27W (MA-ON), LOCATED APPROXIMATELY 668 NM EAST-NORTHEAST OF ANDERSEN AFB, GUAM HAS TRACKED WEST- NORTHWESTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS FLARING CONVECTION ALONG THE EASTERN SEMI-CIRCLE OF A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC). THE EXPOSED NATURE OF THE LLCC PROVIDES GOOD CONFIDENCE IN THE CURRENT POSITION. THE MSI LOOP AND A 100751Z GPM 89GHZ IMAGE CONTINUE TO SHOW AN ORGANIZED LLCC WITH WELL-DEFINED CLOUD LINES EVIDENT EVERYWHERE EXCEPT THE SOUTHWESTERN QUADRANT. THE GPM IMAGE ALSO SHOWS DEEP CURVED CONVECTION ALONG THE EASTERN SIDE WRAPPING INTO THE CENTER. THE INTENSITY IS ASSESSED AT 30 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T2.0 (30 KNOTS) FROM ALL AGENCIES AND REFLECTS THE LIMITED CHANGE IN THE STRUCTURE SINCE THE LAST WARNING. ENVIRONMENTAL CONDITIONS ARE MARGINALLY-FAVORABLE WITH A POINT SOURCE LOCATED TO THE EAST OF THE LLCC PRODUCING WEAK DIVERGENT OUTFLOW AND LOW TO MODERATE (10-15 KNOT) VERTICAL WIND SHEAR (VWS) OVER THE CENTER. TD 27W IS TRACKING NORTHWESTWARD UNDER THE INFLUENCE OF A DEEP LAYERED SUB-TROPICAL RIDGE ENTRENCHED TO THE NORTHEAST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING. B. TD MA-ON WILL CONTINUE TRACKING TOWARD THE NORTHWEST UNDER THE DOMINANT STEERING RIDGE TO THE NORTHEAST. UPPER-LEVEL CONDITIONS ARE EXPECTED TO REMAIN MARGINALLY-FAVORABLE OVER THE NEXT 24 HOURS ALLOWING FOR A SLIGHT INTENSIFICATION. AFTERWARDS, VWS WILL BEGIN TO INCREASE AS THE CYCLONE APPROACHES THE STRONG ZONAL MID-LATITUDE WESTERLIES. THE UNFAVORABLE ENVIRONMENT WILL LEAD TO THE SYSTEMS DISSIPATION BY TAU 72 OR POSSIBLY SOONER. DYNAMIC MODEL GUIDANCE REMAINS IN GOOD AGREEMENT ON THE NORTHWESTWARD TRACK, LENDING TO HIGH CONFIDENCE IN THE JTWC FORECAST.// NNNN NNNN