MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 07W (SEVEN) WARNING NR 05// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION (TD) 07W (SEVEN), LOCATED APPROXIMATELY 1155 NM EAST-SOUTHEAST OF GUAM, HAS TRACKED SOUTHEASTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY SHOWS THE SYSTEM HAS MAINTAINED OVERALL CONVECTIVE SIGNATURE. THE INITIAL POSITION IS BASED ON A LOW REFLECTIVITY CIRCULATION ON A 071559Z AMSU-B MICROWAVE IMAGE WITH POOR CONFIDENCE. THE INITIAL INTENSITY IS BASED ON CONGRUENT DVORAK ESTIMATES FROM PGTW, KNES, AND RJTD. UPPER LEVEL ANALYSIS INDICATES TD 07W IS WELL SOUTH OF THE RIDGE AXIS IN AN AREA OF MODERATE (20-25 KNOT) VERTICAL WIND SHEAR. HOWEVER, A ROBUST EQUATORWARD OUTFLOW CHANNEL IS PROVIDING VENTILATION TO THE ASSOCIATED CONVECTION. THE CYCLONE IS DRIFTING SOUTHEASTWARD WITH THE LOW LEVEL GRADIENT FLOW. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TD 07W IS FORECAST TO CONTINUE ON AN EASTWARD TRACK AND INTENSIFY SLIGHTLY OVER THE NEXT 12 HOURS. AFTERWARDS, A BUILDING SUBTROPICAL RIDGE (STR) TO THE NORTH WILL BEGIN TO ASSUME STEERING AND EVENTUALLY REDIRECT THE SYSTEM TOWARD THE NORTHWEST BY TAU 36. AS THE SYSTEM MAKES THE TURN, UPPER-LEVEL CONDITIONS ARE EXPECTED TO BECOME MORE FAVORABLE FOR INTENSIFICATION. THESE FACTORS, ALONG WITH PASSAGE OVER VERY WARM WATER, SHOULD SUPPORT AN INCREASE TO TYPHOON INTENSITY BY TAU 72. C. BEYOND TAU 72, TD 07W WILL MOVE NORTHWESTWARD UNDER THE CONTINUED STEERING INFLUENCE OF THE STR. GENERALLY FAVORABLE UPPER-LEVEL ENVIRONMENTAL CONDITIONS WILL PERSIST, SUPPORTING ADDITIONAL INTENSIFICATION THROUGH THE END OF FORECAST. THE JTWC FORECAST REMAINS CLOSE TO THE MULTI-MODEL CONSENSUS, BUT DUE TO THE UNCERTAINTY OF THE STORM MOTION DURING THE INTIAL PHASE, THERE IS OVERALL A LOW CONFIDENCE IN THE JTWC TRACK FORECAST.// NNNN NNNN