Tag Archives: 06W

Typhoon Nida Makes Landfall Near Hong Kong

Typhoon Nida made landfall on Monday near Hong Kong on the coast of China.  At 5:00 p.m. EDT on Monday the center of Typhoon Nida was located at latitude 22.8°N and longitude 114.4°E which put it about 50 miles (80 km) east-northeast of Hong Kong.  Nida was moving toward the northwest t 13 m.p.h.  The maximum sustained wind speed was 95 m.p.h. (155 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 963 mb.

Typhoon Nida made landfall on the southeast coast of China just to the north of Hong Kong.  The core of Nida is large and the typhoon is capable of causing wind damage on a regional scale.  Wind blowing toward the coast could also generate a storm surge until Typhoon Nida moves farther inland.  However, very heavy rain and fresh water flooding are much greater risks as Nida moves farther inland over China.

A subtropical ridge north of Nida is steering the typhoon toward the northwest and that general motion is expected to continue for the next several days.  The ridge will steer Nida farther inland over southeastern China.  Typhoon Nida’s fairly slow motion and large size mean that heavy rain could fall over an expansive area.  The risk for flooding will continue as Nida moves inland.

Typhoon Nida Brushes Luzon and Heads for Hong Kong

Typhoon Nida brought wind and rain to northern Luzon on Sunday as it continued to move toward Hong Kong on the coast of China.  At 11:00 p.m. EDT on Sunday the center of Typhoon Nida was located at latitude 20.4°N and longitude 118.3°E which put it about 340 miles (545 km) east-southeast of Hong Kong.  Nida was moving toward the west-northwest at 17 m.p.h. (27 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 974 mb.

The Hurricane Intensity Index (HII) for Typhoon Nida is 10.4.  The Hurricane Size Index (HSI) is 13.1 and the Hurricane Wind Intensity Size Index (HWISI) is 23.5.  These indices suggest that Typhoon Nida will be capable of causing minor wind damage on a regional scale.

The structure of Typhoon Nida changed significantly on Sunday.  The primary rainband wrapped around the core of the circulation and a very large eye was created at the center.  The diameter of the eye is approximately 50 miles (80 km).  The strongest winds are occurring in the ring of thunderstorms that surrounds the eye.  Other spiral bands of thunderstorms are rotating around the large eye.  The thunderstorms were generating upper level divergence which pumped out mass and allowed the surface pressure to decrease.

Typhoon Nida is in an environment that would favor intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  Easterly winds are blowing in the upper levels, but there is not much vertical wind shear.  The large size of the eye of Nida is the major factor inhibiting intensification.  It takes more energy to increase the wind speed in a large typhoon than it does in a smaller storm.  If the eye contracts, then Typhoon Nida could intensify more before it makes landfall.

A subtropical ridge north of Nida is steering the typhoon toward the west-northwest and that general motion is expected to continue for another day or so.  On its anticipated track Typhoon Nida will be very near Hong Kong in about 24 hours.

As mentioned above, the large size of Typhoon Nida means that it will be capable of causing wind damage on a regional scale.  In addition, Typhoon Nida will be capable of creating a significant storm surge when it moves into the coast of China.  A large slow moving typhoon like Nida will also produce heavy rain and flooding as it moves inland.

Intensifying Tropical Storm Nida Nears Northern Philippines

Tropical Storm Nida intensified on Saturday as it slowly approached the northern portion of Luzon in the Philippines.  At 5:00 p.m. EDT (2100 UTC) the center of of Tropical Storm Nida was located at latitude 16.5°N and longitude 123.8°E which put it about 245 miles (395 km) east-northeast of Manila, Philippines.  Nida was moving toward the west-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 50 m.p.h. (95 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 989 mb.

The circulation of Tropical Storm Nida has become increasingly well organized during the past 24 hours.  A primary rainband wraps about two thirds of the way around the western and southern sides of the center of circulation.  Additional spiral bands of thunderstorms are developing outside the core of the circulation.  Rising motion associated with the convection is generating upper level divergence which is pumping out mass and allowing the surface pressure to decrease.

Tropical Storm Nida is moving through an environment that is very favorable for further intensification.  It is moving over water where the Sea Surface Temperature (SST) is near 31°C.  Nida is beneath an upper level ridge where the upper level winds are light and there is little vertical wind shear.  Very warm SSTs and little wind shear will allow the circulation of Tropical Storm Nida to consolidate further and it should continue to intensify.  Nida could intensify rapidly once an eye starts to form at the center of circulation.  Tropical Storm Nida will move near or over the northeastern part of Luzon.  Interaction with land could slow or temporarily stop the intensification.  However, Tropical Storm Nida should intensify further after it move wests of the Philippines.

A subtropical ridge north of Nida is steering the tropical storm toward the west-northwest and that general motion is expected to continue.  On its anticipated track Tropical Storm Nida could move over the northern part of Luzon during the next 12 to 24 hours.  Nida could approach the area around Hong Kong as a typhoon in about 48 hours.

The primary threats posed by Tropical Storm Nida to the Philippines are locally heavy rain and flash floods.  Tropical Storm Nida could generate very heavy rain in locations where the circulation causes the wind to blow up the slopes of mountains.  Heavy rain falling on steep terrain in those locations could also cause flash flooding.  Nida could be a typhoon by the time it reaches the part of China near Hong Kong.  Nida will be capable of producing some wind damage and storm surge in addition to heavy rain and flooding when it reaches the coast of China.