Typhoon Mirinae will hit the Luzon province in the Philippines. It’s possible that Mother Nature may also erupt a volcano at the same time. The Typhoon Mirinae Forecast Track is very similar to that of Typhoon Ketsana. The difference will be that it’s forward momentum will continue and therefore will not remain over the Philippines for an extended period of time.

The Typhoon Mirinae Forecast Track takes it into the Philippines almost due east of Manila and it re-emerges in the South China Sea almost due west of Manila. There is some sense of continuity with the computer models. The NOGAPS calls for a landfall at just around 12Z October 30 as a tropical cyclone with a central pressure a shade less than 992 mb. The NOGAPS suggests that the center of circulation will be just west of Manila by 06Z October 31 with a pressure of something less than 1000 mb. Now, the GFS is a bit different as it wants to weaken the storm prior to landfall to less than 1000 mb and has it exit as a 1004 mb low. It too calls for a landfall in the neighborhood of 12Z October 30 with it moving offshore west of Manila by 6Z October 31. A few days later, Mirinae is forecast to weaken somewhat over colder water in the South China Sea before making a second landfall in Vietnam before moving into Cambodia.

The official forecast track as of 00Z October 30 from the Joint Typhoon Warning Center calls for Typhoon Mirinae to make landfall east of Manila sometime between 12z and 18Z on October 30 and has it offshore of Manila by about 02Z October 31. Other models must call for the faster speed as the NOGAPS and GFS call for the storm to be over land for about 18 hours whereas the boys at the JTWC are thinking more along the lines of 12 hours. The folks in the Philippines will be hoping that the JTWC is correct because the faster pace will reduce the time of heavy rain over the island. Still, several hours of heavy rain will be in the cards and winds will initially be running around 90 kts (100 mph) at landfall with higher gusts. The storm’s forward speed will also mean that typhoon strength winds will be felt by everyone in the path of the center of circulation because, though weakened, it will still be a minimal typhoon when it moves back offshore in all liklihood. Over 100,000 Filipinos remain in evacuation shelters from the effects of Typhoon Ketsana and Typhoon Parma which collectively killed over 900 people. Many have been affected by the rapid spread of the disease known as Leptospirosis. The government is warning for the potential for flooding and landslides so more people have been evacuated from vulnerable locations.

If that is not enough for the Philippines….as Typhoon Mirinae makes landfall, Mount Mayon in the Philippines is making noises and there is a fear that Mount Mayon, the most active volcano in the Philippines may erupt while Mirinae is over the island or shortly thereafter. The active volcano is one of many volcanic peaks in the Philippines and has been responsible for well over a dozen volcanic earthquakes and has begun spewing ash and sulpher dioxide into the air. It last had an ash eruption on September 15. Officials have been trying to get a look at the crater to determine if the dome forming there is indeed a lava dome or if its simply a case of magma below the surface pushing old rock to the surface. Trouble is, they can’t make aerial examinations of the crater on top of Mount Mayon due to cloud cover and with the advance of Typhoon Mirinae, which the Philippines weather authorities designated as Typhoon Santi (why they have different names is a mystery to me), they won’t be able to make any observations. So, Philippines Volcano Monitoring authorities issued a level 2 alert warning the residents around the volcano and are enforcing a strict ban on people entering a zone around Mayon.

If they issue a level 3 alert, then some 30,000 residents around the volcano will have to be evacuated. There is great concern here because Mayon’s crater holds over 200,000 cubic feet of rocks. There is fear of an eruption with lava flows. Even of greater concern is the threat of a Lahar,the fast moving flow of mud, water and perhaps lava that can sweep down from volcanoes. Heavy rains may enhance that threat and official say that in a worst case scenario, they may have to evacuate some 300,000 people from Lahar zones. However, Mount Mayon is pretty far south of the forecast landfall location. Should Mirinae make landfall as the JTWC suggests, then the greatest rainfall should be well north of Mount Mayon.

WDPN32 PGTW 300300 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 23W (MIRINAE) WARNING NR 17// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. TYPHOON MIRINAE HAS TRACKED WEST-SOUTHWESTWARD AT 17 KNOTS OVER THE PAST 12 HOURS AND SUSTAINED AN INTENSITY OF 90 KNOTS. THOUGH THE CYCLONE STILL HAS SOME WESTWARD BLOWING CONVECTION, INDICATING THE PRESENCE OF EASTERLY VERTICAL WIND SHEAR, A SMALL ANTICYCLONE ALOFT HAS ENABLED CONTINUED RADIAL OUTFLOW. WHILE MIRINAE WAS PREVIOUSLY MAINTAINING A CENTRAL DENSE OVERCAST PATTERN THAT MADE POSITIONING USING INFRARED AND VISIBLE IMAGERY DIFFICULT, IT HAS RECENTLY STARTED TO DEVELOP MORE OF A BANDING EYE FEATURE. THEREFORE, IN COMBINATION WITH THE 292259Z 37 GHZ SSMIS MICROWAVE IMAGE, THE CURRENT POSITION IS PLACED WITH GOOD CONFIDENCE. SIMILARLY, THE CURRENT INTENSITY IS BASED ON CONSISTENT DVORAK ESTIMATES FROM PGTW, RJTD AND KNES OF 90 KNOTS. 3. FORECAST REASONING. A. THE FORECAST REASONING HAS NOT CHANGED SINCE THE PREVIOUS PROGNOSTIC REASONING BULLETIN. B. TYPHOON MIRINAE WILL CONTINUE TRACKING WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE WELL-ESTABLISHED SUBTROPICAL RIDGE. THE SYSTEM IS EXPECTED TO MAKE LANDFALL IN CENTRAL LUZON AROUND TAU 18 AND SLOW SLIGHTLY (BY APPROXIMATELY 2-3 KNOTS) IN FORWARD TRACK SPEED WHILE DECREASING BY 15 TO 20 KNOTS IN INTENSITY. AFTER TAU 24, MIRINAE IS EXPECTED TO ENTER THE SOUTH CHINA SEA ON A WESTWARD TRACK AND CONTINUE TO STEADILY WEAKEN UNDER THE INFLUENCE OF INCREASINGLY UNFAVORABLE VERTICAL WIND SHEAR ASSOCIATED WITH THE COMBINATION OF EASTERLY FLOW SOUTH OF THE SUBTROPICAL RIDGE AXIS (MID-LEVELS) AND NORTHEASTERLY FLOW INDUCED BY AN EARLY-SEASON COLD SURGE. C. MIRINAE WILL MAKE LANDFALL IN SOUTH-CENTRAL VIETNAM JUST AFTER TAU 72 AND WILL DISSIPATE OVER LAND AS A SIGNIFICANT TROPICAL CYCLONE BY TAU 96. THE MODEL GUIDANCE IS IN GOOD AGREEMENT WITH A SOUTHWESTWARD TRACK THROUGH THE SOUTH CHINA SEA. HOWEVER, SOME OF THE MODEL AIDS, INCLUDING THE JAPANESE SOLUTION, TAKE THE SYSTEM JUST SOUTH OF MANILA, PHILIPPINES AND TOWARDS HO CHI MINH CITY, VIETNAM.// NNNN