Tag Archives: Typhoon Noru

Typhoon Noru Approaches Iwo To From Northeast

Typhoon Noru approached Iwo To from the northeast on Friday.  At 5:00 p.m. EDT on Friday the center of Typhoon Noru was located at latitude 27.6°N and longitude 143.0°E which put it about 220 miles (355 km) north-northeast of Iwo To.  Noru was moving toward the southwest at 11 m.p.h. (17 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. (150 km/h).  The minimum surface pressure was 975 mb.

Typhoon Noru retains a well organized circulation.  An eyewall wraps about three quarters of the way around the eye.  There is a break in the ring of thunderstorms on the northeastern rim of the eye.  Bands of showers and thunderstorms are occurring north and east of the center of circulation.  There are fewer showers and thunderstorms south and west of the center of the typhoon.  Thunderstorms near the center are generating some upper level divergence.  The circulation of Typhoon Noru is fairly large.  Winds to tropical storm force extend out about 200 miles (320 km) from the center of circulation.

Typhoon Noru will be moving through an environment that is marginally favorable for intensification.  Noru will move over water where the Sea Surface Temperature (SST) is near 29°C.  An upper level ridge centered west of Japan is producing northeasterly winds which are blowing toward the top of the circulation.  Those northeasterly winds are creating moderate vertical wind shear, which is limiting the upper level divergence to the north of the typhoon.  The wind shear is not strong enough to weaken Typhoon Noru, but it is strong enough to inhibit intensification.  Typhoon Noru may undergo small changes in intensity during the next several days, but it could maintain its status as a typhoon.

The ridge west of Japan is also steering typhoon Noru toward the southwest and that general motion is expected to continue for another day or so.  In 24 to 48 hours Noru is forecast to reach and area where the steering winds are weak and it could stall near Iwo To.  On its anticipated path Typhoon Noru could bring an extended period of strong gusty winds and heavy rain to Iwo To.

Tropical Storm Nesat Forms Southeast of Taiwan

Tropical Storm Newsat formed southeast of Taiwan on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Nesat was located at latitude 18.0°N and longitude 127.5°E which put it about 620 miles (1000 km) southeast of Taipei, Taiwan.  Nesat was moving toward the north at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 988 mb.

A well organized surface circulation formed in an area of thunderstorms southeast of Taiwan on Wednesday.  A strong cluster of thunderstorms formed south of the center of circulation.  Additional bands of showers and thunderstorms developed in the western and southern portions of Tropical Storm Nesat.  There were few thunderstorms in the eastern half of the circulation.  More thunderstorms appeared to be forming near the core of the circulation in recent hours.  The thunderstorms in the core were generating upper level divergence which was pumping out mass.

Tropical Storm Nesat will be moving through an area that is favorable for intensification.  Nesat will move over water where the Sea Surface Temperature is near 31°C.  Tropical Storm Nesat is beneath the northeastern part of an upper level ridge.  The ridge is producing northeasterly winds which are blowing toward the top of the circulation.  Those winds are causing some vertical wind shear and the shear could be the reason for the asymmetrical distribution of thunderstorms.  Tropical Storm Nesat could move under the axis of the upper level ridge where the winds are weaker.  In that case the shear would be less and Nesat could intensify more quickly.  Tropical Storm Nesat is likely to intensify into a typhoon during the next 24 hours.

Tropical Storm Nesat is moving around a weak area in a subtropical ridge, which is allowing the tropical storm to move toward the north.  The ridge is forecast to strengthen and when that happens it will steer Nesat more toward the west.  On its anticipated track Tropical Storm Nesat could approach Taiwan in about three days.  Nesat could be a strong typhoon when it nears Taiwan.

Elsewhere in the Western North Pacific Typhoon Noru has turned back toward the west.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Noru was located at latitude 30.6°N and longitude 151.2°E which put it about 770 miles (1240 km) east-northeast of Iwo To.  Noru was moving toward the west at 19 m.p.h. (31 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. (150 km/h).  The minimum surface pressure was 978 mb.

A subtropical ridge north of Typhoon Noru is steering the typhoon toward the west.  A general westerly motion is forecast to continue for several more days.  Noru could reach an area of weaker steering winds in a few days and its motion may slow.  On its anticipated track Typhoon Noru could approach Iwo To in three or four days.

Tropical Storm Sonca Near Landfall in Vietnam.

Tropical Storm Sonca neared a landfall on the coast of Vietnam on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Sonca was located at latitude 16.7°N and longitude 108.2°E which put it about 60 miles (95 km) east-northeast of Hue, Vietnam.  Sonca was moving toward the west at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 991 mb.

The circulation of Tropical Storm Sonca is fairly small.  Winds to tropical storm force only extend out about 60 miles (95 km) from the center of circulation.  A subtropical ridge north of Sonca is steering the tropical storm toward the west and that general motion is expected to continue for another 24 to 36 hours.  On its anticipated track the center of Tropical Storm Sonca will make landfall north of Hue, Vietnam in a few hours.

Tropical Storm Sonca will bring gusty winds, locally heavy rain and the potential for floods when it makes landfall.  Sonca will continue to move inland over central Vietnam, central Laos and northeastern Thailand.  Sonca could continue to produce locally heavy rain over those areas as it moves inland and weakens.

Elsewhere in the Western North Pacific the circulations of Typhoon Noru and Tropical Storm Kulap are interacting east-southeast of Japan.  At 11:00 p.m. EDT on Monday the center of Typhoon Noru was located at latitude 25.9°N and longitude 157.0°E which put it about 1330 miles (2150 km) east-southeast of Tokyo, Japan.  Noru was moving toward the east at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 95 m.p.h. (155 km/h) and there were gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 966 mb.

At 11:00 p.m. EDT the center of Tropical Storm Kulap was located at latitude 32.9°N and longitude 155.8°E which put it about 1095 miles (1765 km) east-southeast of Tokyo, Japan.  Kulap was moving toward the west at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1000 mb.

Typhoon Noru and Tropical Storm Kulap are close enough to each other to rotate cyclonically around a point between them in what is called the Fujiwhara effect.  Typhoon Noru is the much larger and stronger circulation and upper level outflow from Noru is causing vertical wind shear over Tropical Storm Kulap.  If the two tropical cyclones move closer to each other, it is possible that the circulation of Kulap could be absorbed by the larger, more powerful circulation of Typhoon Noru.