Tag Archives: 18W

Tropical Storm Mawar Nears Landfall in China

Tropical Storm Mawar moved closer to a landfall in China on Saturday.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Mawar was located at latitude 22.2°N and longitude 116.4°E which put it about 150 miles (240 km) east of Hong Kong.  Mawar was moving toward the west-northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 55 m.p.h. (90 km/h) and there were wind gusts to 70 m.p.h. (110 km/h).  The minimum surface pressure was 989 mb.

The circulation of Tropical Storm Mawar is very asymmetrical.  Most of the thunderstorms are located south of the center of circulation.  A primary rainband is just south of the center of circulation and there are several other bands farther south of the center.  Recent visible satellite images suggest that the eastern end of the primary rainband could be trying to wrap around the center.  Thunderstorms in the primary rainband were generating some upper level divergence which was pumping mass away to the southwest of the tropical storm.

Tropical Storm Mawar will move through an environment that is somewhat favorable for intensification during the next 12 to 18 hours.  Mawar will move over water where the Sea Surface Temperature is near 29°C.  An upper level ridge centered over China is producing northeasterly winds which are blowing toward the top of the circulation.  Those winds are generating moderate vertical wind shear.  Those winds may also be the reason for the asymmetrical distribution of thunderstorms.  Mawar could intensify before it makes landfall in China.

Tropical Storm Mawar is being steered slowly toward the west-northwest by a ridge near Japan.  That general motion is expected to continue for the next several days.  On its anticipated track Tropical Storm Mawar will make landfall in China east of Hong Kong in 12 to 18 hours.  Mawar will bring gusty winds and locally heavy rain to parts of Guangdong province.  The rain could contribute to flooding in some locations.  Mawar is likely to weaken steadily after it makes landfall.

Typhoon Malakas Bringing Gusty Winds and Rain to Shikoku and Honshu

Typhoon Malakas is bringing wind and rain to coastal areas of Shikoku and Honshu.  At 11:00 p.m. EDT on Monday the center of Typhoon Malakas was located near latitude 33.4°N and longitude 134.7°W which put it about 90 miles (145 km) southwest of Osaka, Japan.  Malakas was moving toward the northeast at 25 m.p.h. (40 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 979 mb.

The structure of Typhoon Malakas is starting the transition from a tropical cyclone to an extratropical cyclone.  It retains an eye, but the thunderstorms in the southern part of the eyewall are thinning.  Most of the other thunderstorms are in rainbands north of the center of circulation.  Cooler, drier air is wrapping around the southern side of the circulation.  The strongest winds are occurring over the water near the center of circulation.  Heavy rain is falling over eastern Shikoku and southwestern Honshu near Osaka and Nagoya.

Although Typhoon Malakas is moving over water where the Sea Surface Temperature is near 28°C, it will continue to weaken as it makes the transition to an extratropical cyclone.  An upper level trough west of Japan is producing southwesterly winds which are blowing across the top of the circulation.  Also, almost half of the circulation is moving over land and the center will move over coastal sections of Honshu.  Increasing vertical wind shear and the added friction caused by the land will weaken Malakas to a tropical storm on Tuesday.

The upper level trough is steering Typhoon Malakas quickly toward the northeast and that general motion is expected to continue.  On its anticipated track Typhoon Malakas will pass south of Osaka and Nagoya.  The center of then Tropical Storm Malakas will move near Tokyo in about 18 hours.  Malakas will continue to bring gusty winds to coastal parts of Honshu.

Powerful Typhoon Malakas Nearing Kyushu

Powerful Typhoon Malakas moved steadily closer to Kyushu on Sunday.  At 11:00 p.m. EDT on Sunday the center of Typhoon Malakas was centered at latitude 29.7°N and longitude 127.9°E which put it about 210 miles (340 km) southwest of Kagoshima, Japan.  Malakas was moving toward the east-northeast at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 948 mb.

The circulation of Typhoon Malakas remains well organized and it is taking on the typical structure of a strong tropical cyclone that is starting to recurve.  The size of the eye increased during the past 24 hours.  The eye is surrounded by a ring of strong thunderstorms which is thinner south of the eye.  There are several strong rainbands, but they are primarily in the northern half of the circulation.  The circulation is beginning to pull drier air around the southern side of Malakas which is why the rainbands in that part of the typhoon are weaker.  Thunderstorms in the core of Typhoon Malakas are generating upper level divergence that is pumping out mass toward the northeast.

Typhoon Malakas is moving through an environment that should allow it to maintain its intensity during the next few hours.  It is moving over water where the Sea Surface Temperature is near 29°C.  An upper level trough to the west of Japan is generating southwesterly winds which are blowing across the top of the circulation.  However, the vertical wind shear is moderate enough to allow Typhoon Malakas to maintain its intensity in the short term.  When Malakas moves farther to the northeast, it will move into a region where where upper level winds are stronger and the vertical wind shear will increase.  More vertical wind shear and the interaction of the circulation with Kyushu, Shikoku and Honshu will cause Malakas to weaken.

The upper level trough will continue to steer Typhoon Malakas toward the northeast.  On its anticipated track the center of Malakas will be near southwest Kyushu in about 12 hours.  It will be near Shikoku in 20 hours and is could be near Honshu in 30 hours.

Typhoon Malakas will bring strong winds and heavy rain to southwestern Kyushu.  It is likely to still be a typhoon when it passes near the coast of Shikoku.  Malakas could be a tropical storm when it passes south of Kyoto and when it moves near Tokyo in a couple of days.  Malakas could bring wind and heavy rain to the coastal portions of Honshu later this week.

Strong Typhoon Malakas Turns North Toward Southernmost Ryukyu Islands

Strong Typhoon Malakas made the expected turn toward the north on Friday and it began to move parallel to the east coast of Taiwan toward the southwesternmost Ryukyu Islands.  At 5:00 p.m. EDT on Friday the center of Typhoon Malakas was located at latitude 23.4°N and longitude 123.0°E which put it about 100 miles (160 km) southwest of Ishigaki, Japan.  Malakas was moving toward the north at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 937 mb.

Malakas is a strong well organized typhoon.  It has a well formed eye at the center of circulation surrounded by a ring of strong thunderstorms.  Additional bands of thunderstorms are rotating around the core of Malakas and there are more thunderstorms in the southern half of the circulation.  Winds to typhoon force extend out about 35 miles (55 km) in all directions from the center of circulation.  The upper level divergence is strongest to the south of Typhoon Malakas.

Typhoon Malakas is in a very favorable environment.  It is moving over water where the Sea Surface Temperature (SST) is near 29°C.  The upper level winds are not too strong and there is little vertical wind shear.  Typhoon Malakas could intensify a little more during the next 24 hours.  When Typhoon Malakas moves farther north, it will move over cooler SSTs.  In addition there is an upper level trough over eastern China which will cause southwesterly winds and increasing vertical wind shear when Malakas gets farther north.

Typhoon Malakas is moving around the western end of a subtropical ridge and it is likely to continue to move north for another 24 hours or so.  In about a day, the upper level trough over eastern China will start to turn Malakas toward the northeast.  On its anticipated track Typhoon Malakas could approach southwestern Kyushu in about three days.

The center of Typhoon Malakas is passing east of Taiwan.  Some of the rainbands in the western part of the circulation will move over Taiwan, but the core of the typhoon where the strongest wind is occurring will stay east of there.  The center of Malakas will pass west of Ishigaki and Okinawa, but it could move over some of the smaller islands at the very southwestern end of the Ryukyu Islands.  Malakas could cause significant damage on those islands.

Typhoon Malakas Moves Toward Taiwan and the Ryukyu Islands

Typhoon Malakas moved toward Taiwan and the southernmost Ryukyu Islands on Thursday.  At 8:00 p.m. EDT on Thursday the center of Typhoon Malakas was located at latitude 20.1°N and longitude 124.7°W which put it about 285 miles (460 km) south of Ishigaki, Japan.  Malakas was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 956 mb.

The structure of Typhoon Malakas is well organized.  A small eye has been evident intermittently on satellite imagery.  More of the thunderstorms are forming south of the center of circulation, although there are spiral bands of thunderstorms in all quadrants of the circulation.  The thunderstorms in the core of Typhoon Malakas are generating upper level divergence which is pumping out mass in all directions.  The circulation of Typhoon Malakas has been in a rough equilibrium during the past 24 hours and the intensity has remained relatively steady.

Typhoon Malakas is moving through an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  Although there is an upper level trough over China and an upper level low to the northeast of Malakas, the upper level winds around the typhoon are relatively light.  There is not much vertical wind shear.  Typhoon Malakas could strengthen further during the next 24 hours.

Typhoon Malakas is moving around the western end of a subtropical ridge.  Malakas turned more toward the northwest on Thursday.  It is expected to move more toward the north on Friday as is reaches the western end of the ridge.  When Malakas moves farther north, the upper level trough over China will steer the typhoon quickly toward the northeast toward the southern end of Kyushu.  On its anticipated track Typhoon Malakas will be near northeastern Taiwan and the southernmost Ryukyu Islands in about 24 hours.

Typhoon Malakas is smaller than Typhoon Meranti was, but Typhoon Malakas is capable of causing significant wind damage.  It will also bring heavy rain.  Since areas on Taiwan received heavy rain when Typhoon Meranti moved past them, it will take less additional rain to create the potential for flash flooding.

Tropical Storm Etau Develops and Heads Toward Japan

A center of circulation developed within a large area of thunderstorms a few hundred miles south of Japan and the system has been designated Tropical Storm Etau.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Etau was located at latitude 25.3°N and longitude 138.5°E which put it about 720 miles (1160 km) south-southeast of Osaka, Japan.  Etau was moving toward the north at 11 m.p.h. (18 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 998 mb.

Although Tropical Storm Etau does have a low level center of circulation, most of the stronger thunderstorms are located north-northwest of the center.  Etau is moving over water where the Sea Surface Temperatures are warm enough to support intensification.  However, a large upper level trough west of Japan is producing southwesterly winds over the top of the tropical storm.  The circulation appears to be tilting toward the north with height because  of vertical wind shear.  Tilted tropical cyclones are unable to efficiently convert energy to wind speed and intensify.  Etau could intensify a little during the next 24 hours, but then it will run into much stronger upper level winds associated with the upper level trough.  Stronger vertical wind shear will cause Etau to begin to weaken before it reaches Japan.

A subtropical ridge east of Etau is steering it toward the north-northwest and that general motion is expected to continue for the next several days.  On its anticipated track Etau will approach the coast of Japan near Honshu and Shikoku.  Landfall somewhere between Nagoya and Kochi could occur in about 36 hours.  Etau’s biggest impact will be to increase rainfall as it moves inland.