(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 20.0N 155.8E, IS NOW LOCATED NEAR 20.1N 150.6E, APPROXIMATELY 520 NM NORTHEAST OF GUAM. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS PERSISTENT DEEP CONVECTION ASSOCIATED WITH A COLD-CORE LOW PRESSURE SYSTEM. THE MSI CONTINUES TO INDICATE A GOOD MID-TO UPPER-LEVEL CIRCULATION ASSOCIATED WITH THE DISTURBANCE. RECENT SCATTEROMETRY PASSES HAVE INDICATED A CUSP SIGNATURE, MORE REPRESENTATIVE OF AN EASTERLY WAVE, BUT A 070013Z PASS REVEALS A VERY BROAD AND WEAK LOW LEVEL CIRCULATION CENTER (LLCC) IS BEGINNING TO FORM. THE SCATTEROMETRY PASS ALSO REVEALS STRONGER EASTERLY WIND SPEEDS TO THE NORTH OF DISTURBANCE, WHICH DYNAMICAL MODEL FIELDS FORECAST TO WRAP INTO THE SYSTEM IN THE LATER TAUS. ADDITIONALLY, DYNAMIC MODEL FORECAST FIELDS HAVE GENERALLY INCREASED THEIR DEVELOPMENT OF THE DISTURBANCE IN BOTH ORGANIZATION AND INTENSITY. A 062152Z SSMIS MICROWAVE IMAGE REVEALS THE SYSTEM IS STILL FAIRLY ELONGATED WITH FRAGMENTED BANDING ACROSS THE SOUTHERN PERIPHERY. UPPER LEVEL ANALYSIS INDICATES THE DISTURBANCE IS IN A FAVORABLE ENVIRONMENT WITH WEAK VERTICAL WIND SHEAR (5-10 KNOTS) AND GOOD DIVERGENT OUTFLOW. SEA SURFACE TEMPERATURES ARE ALSO FAVORABLE AT 28-30 DEGREES CELSIUS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. DUE TO THE GOOD MID-TO UPPER-LEVEL STRUCTURE, BETTER LOW LEVEL ORGANIZATION, AND DYNAMIC MODEL DEVELOPMENT, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.