Strong Typhoon Nock-ten Makes Landfall in Luzon

Strong Typhoon Nock-ten made landfall in Luzon on Sunday after passing very close to Catanduanes Island.  At 10:00 a.m. EST on Sunday the center of Typhoon Nock-ten was located at latitude 13.5°N and longitude 123.5°E which put it near Tabaco and about 215 miles (345 km) east-southeast of Manila, Philippines.  Nock-ten was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (290 km/h).  The minimum surface pressure was 924 mb.

The circulation of Typhoon Nock-ten is very well organized.  There is a circular eye with a diameter of 14 miles (23 km) at the center of circulation.  A ring of very strong thunderstorms surrounds the eye and the strongest winds are occurring in those thunderstorms.  A second ring of thunderstorms nearly surrounds the inner eye and eyewall.  Nock-ten may have a double eyewall structure.  Additional bands of thunderstorms are occurring outside the core of the circulation.  Winds to typhoon force extend out about 50 miles (80 km) from the center.  The core of Typhoon Nock-ten is generating strong upper level divergence which is pumping out mass in all directions.

The Hurricane Intensity Index (HII) is 31.6.  The Hurricane Size Index (HSI) is 15.5 and the Hurricane Wind Intensity Size Index (HWISI) is 47.1.  The indices indicate that Typhoon Nock-ten is capable of causing regional significant wind damage.

Typhoon Nock-ten will be moving through an atmospheric and oceanic environment that is supportive of tropical cyclones.  When the center of Typhoon Nock-ten is over water, it will move across areas where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is little vertical wind shear.  At times the center of Typhoon Nock-ten will move over portions of southern Luzon.  Nock-ten will weaken each time the center moves over land.  In addition, if an eyewall replacement cycle occurs, the strongest winds will slow as the inner eyewall decays.  However, the broader outer eyewall will cause Nock-ten to retain typhoon intensity for a longer period of time.

A subtropical ridge to the north of Nock-ten is steering the typhoon toward the west and that general motion is expected to continue.  On its anticipated track the center of Typhoon Nock-ten will pass near Naga, Calauag, Lucena, San Pablo,  and Manila in southern Luzon.

Typhoon Nock-ten is capable of doing significant wind damage.  Wind blowing water toward the coast will also create significant storm surges in east facing bays and inlets as the center of Nock-ten approaches.  When the center of circulation moves past parts of southern Luzon, the wind will shift to a southwesterly direction and there will be storms surges in in westerly facing bays and inlets.  Typhoon Nock-ten will produce very heavy rain over parts of southern Luzon.  Serious flooding and mudslides could occur in areas with steeper slopes.