Tag Archives: Laoag

Nesat Intensifies to a Typhoon Northwest of Luzon

Former Tropical Storm Nesat intensified to a typhoon over the South China Sea northwest of Luzon on Sunday morning. At 5:00 a.m. EDT on Sunday the center of Typhoon Nesat was located at latitude 19.6°N and longitude 119.5°E which put it about 125 miles (200 km) northwest of Laoag, Philippines. Nesat was moving toward the west-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 80 m.p.h. (130km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 978 mb.

Former Tropical Storm Nesat rapidly intensified to a typhoon over the South China Sea on Sunday morning. A circular eye with a diameter of 30 miles (50 km) formed at the center of Typhoon Nesat. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Nesat’s circulation. The strongest rainbands were in the western and northern parts of the circulation. Storms near the core of Nesat generated upper level divergence that pumped mass away from the typhoon. Winds to typhoon force extended out 40 miles (65 km) from the center of Nesat’s circulation. Storms to tropical storm force extended out 150 miles (240 km) from the center of circulation.

Typhoon Nesat will move through an environment favorable for intensification during the next 24 hours. Nesat will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the southern part of an upper level ridge that extends over the Western North Pacific Ocean to eastern China. The ridge will produce easterly winds that will cause some vertical wind shear. The wind shear will inhibit intensification, but Typhoon Nesat will strengthen during the next 24 hours. Nesat could continue to intensify rapidly during the next few hours.

Typhoon Nesat will move around the southern side of a surface high pressure system over the Western North Pacific Ocean and eastern China. The high pressure system will steer Nesat toward the west during the next several days. On its anticipated track Typhoon Nesat could be south of Hong Kong within 48 hours.

Powerful Typhoon Mangkhut Hits Northern Luzon

Powerful Typhoon Mangkhut hit northern Luzon on Friday.  At 5:00 p.m. EDT on Friday the center of Typhoon Mangkhut was located at latitude 18.2°N and longitude 121.5°W which put it about 60 miles (95 km) east of Laoag, Philippines.  Mangkhut was moving toward the west-northwest at 21 m.p.h. (35 km/h).  The maximum sustained wind speed was 165 m.p.h. (270 km/h) and there were wind gusts to 200 m.p.h. (320 km/h).  The minimum surface pressure was 908 mb.

Mangkhut is a large and dangerous typhoon.  Winds to typhoon force extend out about 110 miles (175 km) from the center of circulation.  Winds to tropical storm force extend out about 330 miles (530 km) from the center.  The outer rainbands around Typhoon Mangkhut stretch from Manila, Philippines to southern Taiwan.

The Hurricane Intensity Index (HII) is 36.8.  The Hurricane Size Index (HSI) is 38.5 and the Hurricane Wind Intensity Size Index (HWISI) is 75.3.  Typhoon Mangkhut is bigger than Hurricane Katrina was when Katrina was a Category 5 hurricane on the Saffir-Simpson Scale over the Gulf of Mexico in 2005.  Typhoon Mangkhut has the potential to cause extensive catastrophic damage over parts of Luzon.

Typhoon Mangkhut will cause extensive catastrophic wind damage over northern Luzon.  It will also drop heavy rain and there will be flash floods.  The flooding will be worse in areas of steeper slopes.  There will be a significant storm surge on the coast of extreme northeastern Luzon.

Typhoon Mangkhut will weaken while it crosses northern Luzon.  Mangkhut will then move quickly off to the west-northwest. On its anticipated track Typhoon Mangkhut could be near Hong Kong in about 30 hours.

Tropical Storm Ampil Moves Over Okinawa

Tropical Storm Ampil moved over Okinawa on Friday night.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Ampil was located at latitude 27.3°N and longitude 127.4°E which put it about 25 miles (40 km) north-northwest of Okinawa.  Ampil was moving toward the northwest at 21 m.p.h. (34 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 990 mb.

Drier air continued to circulated around Tropical Storm Ampil on Friday and the drier air prevented Ampil from intensifying.  Several bands of stronger thunderstorms were occurring northeast of the center of circulation and the strongest winds were occurring in those bands.  The bands in other parts of Tropical Storm Ampil consisted primarily of the showers and low clouds.  There was a distinct low level center of circulation, but there were few thunderstorms near the center.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.

Tropical Storm Ampil is unlikely to intensify significantly before it makes landfall in China.  Ampil will move over water where the Sea Surface Temperature is near 28°C.  So, there will be enough energy in the ocean to support intensification.  There is a chance for some intensification on Saturday, if more thunderstorms develop near the center of circulation.  However, the drier air will inhibit the formation of taller thunderstorms and that will limit possible intensification..

Tropical Storm Ampil will move south of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Ampil quickly toward the northwest.  On its anticipated track Tropical Storm Ampil will move quickly away from Okinawa and the Ryukyu Islands.  Ampil could approach the coast of China near Shanghai in about 24 hours.  Tropical Storm Ampil will bring gusty winds and locally heavy rain to the region of China around Shanghai.

Elsewhere over the Western North Pacific Ocean Tropical Depression 13W formed west of northern Luzon.  At 11:00 p.m. EDT on Friday the center of Tropical Depression 13W was located at latitude 18.0°N and longitude 118.9°E which put it about 140 miles (225 km) west of Laoag, Philippines.  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 998 mb.  The depression could bring locally heavy rain and cause flash floods over Luzon during the weekend.