Issued At: 5:00 a.m., 15 June 2009
Valid Beginning:5:00 a.m. today until 5:00 a.m. tomorrow
At 2:00 a.m. today, the Active Low Pressure Area (ALPA) was estimated based on satellite and surface data at 240 kms East of Bicol Region (14.0°N 125.5°E) embedded along the Intertropical Convergence Zone (ITCZ) affecting Central and Southern Luzon, Visayas and Mindanao.
Central and Southern Luzon, Visayas and Mindanao will experience mostly cloudy skies with scattered rainshowers and thunderstorms becoming cloudy over the eastern section of Central and Southern Luzon with scattered to widespread rains. The rest of the country will be partly cloudy to at times cloudy with isolated rainshowers or thunderstorms mostly in the afternoon or evening. Light to moderate winds blowing from the southwest to south will prevail over Northern Luzon and coming from the southwest and west over the rest of the country. The coastal waters throughout the archipelago will be slight to moderate except during thunderstorms.
THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.0N 127.3E, IS NOW LOCATED NEAR 14.7N 123.9E, APPROXIMATELY 177 NM EAST OF MANILA, PHILIPPINES. ANIMATED INFRARED SATELLITE IMAGERY SHOWS A SIGNIFICANT DECREASE IN CONVECTION NEAR THE LOW LEVEL CIRCULATION CENTER (LLCC). A 140927Z ( 5:27 a.m. June 15) QUIKSCAT PASS INDICATES THE LLCC IS ELONGATED AND EMBEDDED IN THE MONSOON TROUGH WITH WINDS BETWEEN 10 AND 15 KNOTS NEAR THE CENTER. A 141745Z AMSU-B IMAGE REVEALS A WELL DEFINED SURFACE CIRCULATION SIGNATURE WITH MINIMAL CONVECTION ASSOCIATED WITH THE LLCC. UPPER AIR OBSERVATIONS FROM RPMT AND RPLI SHOW SIGNIFICANT AMOUNTS OF DRY AIR BETWEEN 800 MB AND 500 MB IN THE REGION. THE UPPER LEVEL ENVIRONMENT REMAINS FAVORABLE WITH LOW AMOUNTS OF VERTICAL WIND SHEAR, HOWEVER THE SYSTEM HAS MOVED TO THE WEST OF AN UPPER LEVEL RIDGE AXIS AND HAS LOST OUTFLOW TO A TROPICAL UPPER TROPOSHERIC TROUGH TO THE EAST. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 12 TO 17 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1009 MB. DUE TO LACK OF CONVECTION, DRY AIR INTRUSION AND A WEAKENING LLCC, THE POTENTIAL FOR DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS DOWNGRADED TO POOR. SEE REF A (WTPN21 PGTW 142200) FOR FURTHER DETAILS.