Typhoon Mirinae is well west of the Philippines(see discussion below). Reports are that the number of deaths in the Philippines rose to 14 with significant flooding reported in numerous villages. See CNN story and video here. I still can’t get any reports concerning activity at Mount Mayon so I suppose that means it is behaving itself. There is another tropical cyclone (see discussion below) trying to get going to the east of the Philippines. A ship near the center of circulation (about 60 nm away) some 595 km east of Manila reported a pressure of 1007.5 mb which really isn’t that low. I have yet to see any data that supports any huge development but the JTWC still gives the prospects of significant development at “fair.” Since rain is the issue, I suspect that the biggest problem with this system is its very existance, which was noted several days ago on models. At that time, the models called for this system to move west over the Philippines and so far, the system is following the guidance. It has been observed moving west at 12 knots. While this is not slow, it is of concern because if it continues at this pace and course, it may bring a good chance of rain, perhaps heavy rain for a decent amount of time over the Philippines in the next couple of days.
Typhoon Mirinae has been downgraded to a tropical storm as it moves across the South China Sea on a west southwesterly course. The official track calls for it to continue to move toward Vietnam and make a second landfall on the coast northeast of Ho Chi Minh City. Recently, microwave imagery indicated an eye trying to reform and winds have increased to 50 kts. However, the environment seems in the future to not be too favorable and the most recent observations indicate that the newly formed eye is already deteriorating. Therefore, Vietnam can expect a weak to moderate tropical storm making landfall just prior to 12Z November 2. The remnant of the storm will continue toward Phnom Phen in eastern Cambodia where it may dissipate. The danger is not done though because quite often the remnant of a tropical cyclone can produce an abundance of rain, as exemplified by Tropical Storm Claudette in the 1970′s and more recently Tropical Storm Allison in the Houston area, both of which caused horrific flooding along the upper Texas Coast.
WDPN32 PGTW 011500 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 23W (MIRINAE) WARNING NR 27// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. TROPICAL STORM (TS) 23W (MIRINAE) WEAKENED TO 40 KNOTS AT 0600Z AND, ACCORDING TO RECENT DVORAKS FROM PGTW AND KNES, HAS STRENGTHENED TO 50 KNOTS MORE RECENTLY. A 010955Z SSMI 37H MICROWAVE IMAGE INDICATES A WEAK MICROWAVE EYE, WHICH GENERALLY CORRESPONDS TO A SYSTEM GREATER THAN 45 KNOTS. GIVEN THE LARGE AREA OF CONVECTION THAT HAS BUILT OVER THE LOW LEVEL CIRCULATION CENTER, THE INCREASED DVORAK INTENSITY ESTIMATES, AND THE MICROWAVE EYE, THE INITIAL INTENSITY HAS BEEN INCREASED TO 50 KNOTS. HOWEVER, CLOUD TOP TEMPERATURES HAVE ALREADY BEGUN TO WARM SLIGHTLY AND THE CONVECTION HAS BEGUN TO FLARE. A 011126Z SSMIS MICROWAVE IMAGE ALSO SHOWS THAT THE MICROWAVE EYE FEATURE HAS ALSO BEGUN TO DEGRADE, AND OPEN UP ON THE SOUTH SIDE. THESE OBSERVATIONS ARE INDICATIONS THAT THIS INTENSIFICATION IS SHORT TERM, AND DUE POSSIBLY TO DIURNAL EFFECTS. THE STORM CONTINUES TO TRACK SOUTH OF WEST TOWARDS VIETNAM UNDER THE INFLUENCE OF THE SUBTROPICAL RIDGE TO THE NORTH. 3. FORECAST REASONING. A. THE FORECAST REASONING HAS NOT CHANGED SIGNIFICANTLY SINCE THE PREVIOUS PROGNOSTIC REASONING BULLETIN WITH THE EXCEPTION OF THE SHORT TERM INTENSIFICATION DESCRIBED IN PARA 2.A. THE STORM IS STILL EXPECTED TO WEAKEN PRIOR TO MAKING LANDFALL WITH VIETNAM. B. TS 23W WILL BEGIN TO TRACK WEST-SOUTHWESTWARD AS IT TRACKS ALONG THE SOUTHERN PERIPHERY OF THE MID-LEVEL SUBTROPICAL RIDGE TO THE NORTH. THE NORTHEASTERLY COLD SURGE WILL STRENGTHEN OVER THE NEXT 12 TO 24 HOURS, WHICH WILL ACCOUNT FOR INCREASED VERTICAL WIND SHEAR AND A MORE STABLE ENVIRONMENT. THESE FACTORS WILL CONTRIBUTE TO A SLOW WEAKENING PRIOR TO MIRINAE MAKING LANDFALL WITHIN 24 HOURS. THE STORM IS EXPECTED TO DISSIPATE OVER EASTERN CAMBODIA THERE AFTER, THOUGH THE REMNANT VORTICITY MAY TRACK FURTHER WESTWARD (AS INDICATED BY MANY OF THE OBJECTIVE AID MEMBERS) INTO THE GULF OF THAILAND OR BAY OF BENGAL. REDEVELOPMENT OF THE LLCC DOES NOT APPEAR PROBABLE IN EITHER CASE.// NNNN ABPW10 PGTW 010600 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND /SOUTH PACIFIC OCEANS/010600Z-020600ZNOV2009// REF/A/MSG/NAVMARFCSTCEN PEARL HARBOR HI/010152ZNOV2009// AMPN/REF A IS A TROPICAL CYCLONE WARNING.// RMKS/ 1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA): A. TROPICAL CYCLONE SUMMARY: (1) AT 010000Z, TROPICAL STORM 23W (MIRINAE) WAS LOCATED NEAR 13.9N 115.4E, APPROXIMATELY 545 NM EAST-NORTHEAST OF HO CHI MINH, VIETNAM, AND HAD TRACKED WESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 40 KNOTS GUSTING TO 50 KNOTS. SEE REF A (WTPN32 PGTW 010300) FOR FURTHER DETAILS. (2) NO OTHER TROPICAL CYCLONES. B. TROPICAL DISTURBANCE SUMMARY: (1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.6N 132.3E, IS NOW LOCATED NEAR 16.0N 131.2E, APPROXIMATELY 595 NM EAST OF MANILA, PHILIPPINES. AN OCEANOGRAPHIC RESEARCH SHIP, CALL SIGN MELVILLE, REPORTED 12-KNOT EASTERLIES AND SEA LEVEL PRESSURE AT 1007.5 MB AT 010000Z. MELVILLE IS LOCATED APPROXIMATELY ONE DEGREE TO THE SOUTH-SOUTHEAST OF THE LOW LEVEL CIRCULATION CENTER (LLCC). VARIOUS METSAT IMAGERY, INCLUDING A 312233Z SSMIS, INDICATES PRONOUNCED CURVATURE OF THE CLOUDS PREDOMINATELY WITHIN THE NORTHWEST QUADRANT. DESPITE THIS SIGNATURE THE LLCC IS DIFFICULT TO LOCATE AND THE CONVECTION IS VERY WEAK OVERALL. THE MOST RECENT SCATTEROMETRY DATA (NEARLY 18 HOURS OLD) INDICATE VERY STRONG EASTERLIES TO THE NORTH OF THE LLCC, BUT LIGHT SUPPORTING WESTERLIES TO THE SOUTH. THE UPPER LEVEL ENVIRONMENT REMAINS FAVORABLE WITH LIGHT TO MODERATE VERTICAL WIND SHEAR, AND A JET MAXIMUM TO THE NORTH AIDING (EASTWARD) VENTING. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS FAIR. (2) NO OTHER SUSPECT AREAS. 2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST): A. TROPICAL CYCLONE SUMMARY: NONE. B. TROPICAL DISTURBANCE SUMMARY: NONE.//