MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 27W (KALMAEGI) WARNING NR 011// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION 27W (KALMAEGI), LOCATED APPROXIMATELY 323 NM EAST-NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED NORTHWESTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS A LARGE AREA OF DISORGANIZED, DEEP CONVECTION DISPLACED FROM AN ELONGATED, RAGGED, LOW LEVEL CENTER (LLC). A 150634Z SSMI 85GHZ IMAGE INDICATES SCATTERED, FLARING DEEP CONVECTION OBSCURING THE LLC. THE INITIAL INTENSITY REMAINS ASSESSED AT 30 KNOTS BASED ON MULTI-AGENCY DVORAK INTENSITY ESTIMATES OF T2.0 (30 KNOTS). ENVIRONMENTAL ANALYSIS REVEALS A MARGINAL ENVIRONMENT WITH A GOOD POLEWARD UPPER LEVEL OUTFLOW CHANNEL, WARM SST (29 DEGREES CELSIUS) AND HIGH OCEAN HEAT CONTENT VALUES, OFFSET BY LOW TO MODERATE (15-20 KNOT) VERTICAL WIND SHEAR (VWS), DUE TO OPPOSING LOW LEVEL NORTHEASTERLY SURGE FLOW. TD 27W IS LOCATED IN A LOW STEERING ENVIRONMENT DUE TO A BREAK IN THE SUBTROPICAL RIDGE CAUSED BY A MID-LATITUDE TROUGH PASSING TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TD 27W WILL MEANDER WESTWARD IN THE NEAR TERM IN THE AFOREMENTIONED WEAK STEERING ENVIRONMENT. WITH THE EXCEPTION OF AFUM AND UKMET, GLOBAL MODELS SHOW TD 27W TAKING A NORTHWESTERLY TRACK AT TAU 36 AND SKIRTING ALONG THE NORTHERLY TIP OF LUZON AROUND TAU 72. DUE TO AN OVERALL MARGINALLY FAVORABLE ENVIRONMENT, TD 27W IS EXPECTED TO SLOWLY INTENSIFY TO A PEAK OF 50 KNOTS AT TAU 48 BEFORE DROPPING TO 40 KNOTS DUE TO LAND INTERACTION AS IT PASSES ALONGSIDE LUZON. BASED ON UNCERTAINTY IN THE CURRENT POSITION AND THE COMPLEX STEERING ENVIRONMENT, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE FORECAST TRACK. IN THE NEAR TERM, 27W WILL SLOWLY INTENSIFY TO A PEAK OF 50 KTS AT TAU 48 DUE TO ENHANCED POLEWARD OUTFLOW AND THE SYSTEM TRACKING SLOWLY OVER HIGH OCEAN HEAT CONTENT WATER. HOWEVER, TOTAL INTENSIFICATION WILL BE LIMITED BY HIGH VWS. C. AFTER TAU 72, TD 27W IS EXPECTED TO TURN SOUTHWESTWARD AS IT GAINS STEERING BY A SECOND STR POSITIONED TO THE NORTHWEST. DUE TO SIGNIFICANTLY HIGHER SHEAR VALUES (30-40 KNOTS), WITH THE ADDITION OF COLD, DRY AIR FROM THE NORTHEAST, TD 27W IS EXPECTED TO CONTINUE WEAKENING BEFORE DISSIPATION AT TAU 120. THERE REMAINS SIGNIFICANT ALONG-TRACK UNCERTAINTY AFTER TD 27W TURNS TO THE SOUTHWEST. THE JTWC FORECAST INTENSITY IS BELOW THE MULTIMODEL INTENSITY GUIDANCE DUE TO LAND INTERACTION AND HIGH VWS WHICH WILL CONTINUE TO HAMPER DEVELOPMENT. THERE IS OVERALL LOW CONFIDENCE IN THE EXTENDED PORTION OF THE FORECAST TRACK.// NNNN NNNN