Tag Archives: 09W

Tropical Storm Francisco Drops Heavy Rain on South Korea

Tropical Storm Francisco dropped heavy rain on parts of South Korea on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Francisco was located at latitude 37.4°N and longitude 129.4°E which put it about 25 miles (40 km) southwest of Tonghae, South Korea.  Francisco was moving toward the north at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 999 mb.

After moving across Kyushu on Monday night, the center of Tropical Storm Francisco crossed the Korea Strait and moved northward over eastern South Korea.  The center of Francisco made landfall near Busan (Pusan), South Korea.  Bands of showers and thunderstorms in the northern half of Tropical Storm Francisco dropped heavy rain over parts of South Korea.  The rain could create the potential for flash floods in some locations.  Winds to tropical storm force were occurring in the portions of rainbands over the Sea of Japan.

Tropical Storm Francisco will soon reach a region where the westerly winds in the middle latitudes are blowing.  Those winds will turn Francisco eastward over the Sea of Japan.  Tropical Storm Francisco will move over water where the Sea Surface Temperatures are near 26°C.  However, the westerly winds in the upper levels will create strong vertical wind shear and significant intensification is not expected.  On its anticipated track, Tropical Storm Francisco could reach Hokkaido in about 48 hours.  Francisco could still be a tropical storm at that time.

Elsewhere over the Western North Pacific Ocean, Lekima strengthened into a typhoon southeast of Taiwan and Tropical Storm Krosa intensified south of Iwo To.  At 5:00 p.m. EDT on Tuesday the center of Typhoon Lekima was located at latitude 19.7°N and longitude 127.9°E which put it about 575 miles (925 km) southeast of Taipei, Taiwan.  Lekima was moving toward the northwest at 5 m.p.h. (8 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 967 mb.  Typhoon Lekima could strengthen into the equivalent of a major hurricane and it is forecast to move toward Taiwan and the southern Ryukyu Islands.

At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Krosa was located at latitude 19.9°N and longitude 141.9°E which put it about 360 miles (585 km) south of Iwo To.  Krosa was moving toward the north-northwest at 10 m.p.h. (16 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.  Tropical Storm Krosa is forecast to strengthen into a hurricane and to move toward Iwo To.

Typhoon Francisco Brings Wind and Rain to Kyushu

Typhoon Francisco brought wind and rain to Kyushu on Monday.  At 5:00 p.m. EDT on Monday the center of Typhoon Francisco was located at latitude 32.2°N and longitude 131.4°E which put it about 20 miles (35 km) north of Miyazaki, Japan.  Francisco was moving toward the west-northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 969 mb.

Typhoon Francisco strengthened on Monday as it neared the coast of Kyushu.  A small eye developed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Typhoon Francisco.  The stronger bands were primarily in the eastern half of the circulation.

The core of Typhoon Francisco made landfall on Kyushu just to the north of Miyazaki.  Typhoon Francisco will bring very heavy rain and strong gusty winds to much of Kyushu.  Francisco is forecast to turn toward the northwest and the center of circulation will move across the middle of Kyushu.  Locally heavy rain falling on steep terrain will create the potential for serious flash flooding in some locations.  Rainbands in the eastern half of Typhoon Francisco will also drop locally heavy rain over parts of western Shikoku and western Honshu.

Typhoon Francisco will weaken when it moves across Honshu, but then it will move over the Korea Strait and make another landfall in South Korea.  Francisco will bring gusty winds and locally heavy rain to parts of southern South Korea on Tuesday.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Lekima continue to meander east of Luzon.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Lekima was located at latitude 18.7° and longitude 129.3°E which put it about 670 miles (1085 km) south-southeast of Taipei, Taiwan.  Lekima was moving toward the southwest at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 990 mb.

Tropical Storm Lekima Forms East of Luzon

Tropical Storm Lekima formed east of Luzon on Sunday.  More thunderstorms developed near the center of former Tropical Depression 10W and the Japan Meteorological Agency designated the system as Tropical Storm Lekima.  At 5:00 a.m. EDT on Sunday the center of Tropical Storm Lekima was located at latitude 16.8°N and longitude 131.3°E which put it about 725 miles (1170 km) south-southeast of Okinawa.  Lekima was moving toward the northwest at 6 m.p.h. (10 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 996 mb.

The distribution of thunderstorms around Tropical Storm Lekima was asymmetrical.  Many of the stronger thunderstorms were occurring in bands west of the center of circulation.  There were fewer thunderstorms in the eastern half of the circulation.  Lekima was near the western end of an upper level ridge.  The ridge was producing easterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear and the wind shear was contributing to the asymmetrical distribution of thunderstorms.

Tropical Storm Lekima will move through an environment favorable for intensification during the next few days.  Lekima will move over water where the Sea Surface Temperature is near 31°C.  It will move gradually into a region where the upper level winds are weaker and the vertical wind shear will diminish.  Tropical Storm Lekima will intensify and it could strengthen into a typhoon early next week.

Tropical Storm Lekima will move around the southwestern part of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the northwest.  On its anticipated track Tropical Storm Lekima could approach the southern Ryukyu Islands and Taiwan in about four days.  Lekima could be a typhoon by that time.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Francisco was speeding toward southwestern Japan.  At 5:00 a.m. EDT on Sunday the center of Tropical Storm Francisco was located at latitude 28.9°N and longitude 140.8°E which put it about 710 miles (1150 km) east-southeast of Kagoshima, Japan.  Francisco was moving toward the northwest at 19 m.p.h. (32 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 992 mb.

Tropical Storm Wipha Drops Heavy Rain on Vietnam and China

Tropical Storm Wipha dropped heavy rain on parts of northeastern Vietnam and southern China on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Wipha was located at latitude 21.3°N and longitude 107.4°E which put it about 60 miles (95 km) northeast of Hai Phong, Vietnam.  Wipha was moving toward the west-southwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 990 mb.

The circulation around Tropical Storm Wipha exhibited much greater organization on Friday even though it was moving close to the coast of southern China.  There was a tighter inner core and more thunderstorms were occurring in the bands revolving around the core.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical storm in all directions.  The appearance of Tropical Storm Wipha on satellite imagery was much more circular and symmetrical.  The strongest winds were occurring in the part of the circulation that was still over water.

Tropical Storm Wipha was being steering slowly toward the west-southwest by a subtropical ridge over China and the adjacent waters of the Western North Pacific Ocean.  The combination of greater organization and slow movement will allow Wipha to drop very heavy rainfall over coastal regions of southern China and northern Vietnam.  Prolonged heavy rain will very likely cause flash flooding in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Francisco was strengthening slowly east-southeast of Iwo To.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Francisco was located at latitude 23.2°N and longitude 149.4°E which put it about 545 miles (880 km) east-southeast of Iwo To.  Francisco was moving toward the northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 995 mb.

Tropical Storm Francisco Forms Northeast of the Marianas

Tropical Storm Francisco formed northeast of the Marianas  on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Francisco was located at latitude 20.4°N and longitude 152.4°E which put it about 800 miles (1290 km) east-southeast of Iwo To.  Francisco was moving toward the northwest at 11 m.p.h. (17 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.

A surface low pressure system developed southeast of an upper low north of the Marianas and the Japan Meteorological Agency designated the system as Tropical Storm Francisco.  The distribution of thunderstorms around Francisco was asymmetrical.  Stronger thunderstorms were occurring east of the center of circulation and in a band south of the center of Tropical Storm Francisco.  Bands in other parts of the circulation consisted primarily of showers and lower clouds.  The upper low was producing southwesterly winds which were causing moderate vertical wind shear.  The wind shear was the main factor responsible for asymmetrical distribution of thunderstorms.

Tropical Storm Francisco will move through an environment somewhat favorable for intensification during the next 24 hours.  Francisco will move over water where the Sea Surface Temperature is near 29°C.  The upper low north of the Marianas will continue to cause moderate vertical wind shear during the next day or so.  Tropical Storm Francisco could intensify slowly on Friday.  Francisco will move farther north of the upper low over the weekend.  When it gets farther away from the upper low, the wind shear will diminish and Tropical Storm Francisco could strengthen more quickly.

Tropical Storm Francisco will move southwest of a subtropical ridge over Western North Pacific Ocean.  The ridge will steer Francisco toward the northwest.  On its anticipated track Tropical Storm Francisco could be northeast of Iwo To in about 48 hours.  Francisco could approach southwestern Japan in about fours days.  It is forecast to be a typhoon by that time.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Wipha was moving slowly near the south coast of China.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Wipha was located at latitude 21.1°N and longitude 109.2°E which put it about 25 miles (40 km) south of Beihai, China.  Wipha was moving toward the southwest at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (80 km/h).  The minimum surface pressure was 990 mb.

Tropical Storm Maria Prompts Warning for Guam

Tropical Depression 10W strengthened into Tropical Storm Maria on Wednesday and a Tropical Storm Warning was issued for Guam.  At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Maria was located at latitude 12.7°N and longitude 145.9°E which put it about 95 miles (155 km) southeast of Guam.  Maria was moving toward the north-northwest at 8 m.p.h. (13 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.  Tropical Storm Warnings were in effect for Guam and Rota.  Tropical Storm Watches were in effect for Saipan and Tinian.

The center of circulation in former Tropical Depression 10W became more well organized on Wednesday and the Japan Meteorological Agency designated the system as Tropical Storm Maria.  The circulation was still increasing in organization.  There was a distinct low level center of circulation.  Numerous bands of showers and thunderstorms were revolving around the center of circulation.  Storms near the center were generating upper level divergence which was pumping mass away from the tropical storm.

Tropical Storm Maria will move through an environment very favorable for intensification during the next few days.  Maria will move over water where the Sea Surface Temperature is near 30°C.  Tropical Storm Maria will move under the western end of an upper level ridge that is between two upper level lows which are east and west of the ridge.  The upper level winds will be relatively weak and there will be little vertical wind shear.  The combination of the ridge and two upper level lows will increase the upper level divergence.  Tropical Storm Maria will continue to strengthen.  Maria will become a typhoon later this week.  It could intensify rapidly once an eye forms and the inner core is well developed.

Tropical Storm Maria is moving around the western end of a subtropical ridge which is steering Maria toward the north-northwest.  On its anticipated track the center of Tropical Storm Maria will move near Guam and Rota later today.  A general motion toward the northwest is forecast for the next several days.  Maria could move in the direction of the Ryukyu Islands at the end of the week.

Tropical Storm Maria will bring gusty winds and heavy rain to the southern Mariana Islands.  The strongest winds and heaviest rain will affect Guam and Rota.  Gusty winds and heavy rain will also affect Saipan and Tinian.  Heavy rain could produce flash floods.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Prapiroon was moving over the Sea of Japan.  Prapiroon was bringing wind and rain to the northern Islands of Japan including Hokkaido and Honshu.  At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Prapiroon was located at latitude 39.6°N and longitude 135.6°E which put it about 360 miles (585 km) west-southwest of Misawa, Japan.  Prapiroon was moving toward the northeast at 25 m.p.h. (40 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were winds gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 987 mb.

Typhoon Prapiroon Brings Wind and Rain to Kyushu

Typhoon Prapiroon brought wind and rain to Kyushu on Monday night.  At 11:00 p.m. EDT on Monday the center of Typhoon Prapiroon was located at latitude 32.8°N and longitude 128.6°E which put it about 110 miles (180 km) southwest of Sasebo, Japan.  Prapiroon was moving toward the north-northeast at 17 m.p.h. (27 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 968 mb.

Rainbands on the eastern side of Typhoon Prapiroon were moving over parts of Kyushu.  Those bands were causing gusty winds and they were dropping locally heavy rain.  The circulation of Typhoon Prapiroon was exhibiting the effects of a more midlatitude environment.  Drier air was wrapping around the western and southern portions of the typhoon.  The bands in those parts of Prapiroon consisted primarily of showers and low clouds.  The western portion of the eyewall was also weakening.  There were still strong thunderstorms in the eastern half of the eyewall and that was where the strongest winds were occurring.  Several bands of showers and thunderstorms on the eastern side of the circulation were revolving around the core of Typhoon Prapiroon.

Typhoon Prapiroon will be moving through an environment that will cause it to weaken.  Prapiroon was moving over water where the Sea Surface Temperature was near 26°C.  However, it will move over water where the Sea Surface Temperature is near 24°C when it moves north of Japan.  An upper level trough west of South Korea will produce southwesterly winds which will cause vertical wind shear.  The combination of cooler water and more vertical wind shear will cause Typhoon Prapiroon to weaken to a tropical storm on Tuesday.  Prapiroon could begin a transition to an extratropical cyclone because of the effects of the midlatitude environment.

Typhoon Prapiroon was being steered toward the north-northeast by the upper level trough.  Stronger westerly winds will steer Prapiroon more toward the northeast when it gets north of Japan.  On its anticipated track the center of Typhoon Prapiroon will pass near the northwestern portion of Kyushu.  The center of Prapiroon is forecast to pass between south Korean and Japan and then to move over the Sea of Japan.  Rainbands on the eastern side of Typhoon Prapiroon will cause gusty winds and drop heavy rain over parts of Kyushu.  Heavy could cause flash floods in some locations.  Prapiroon could also bring wind and rain to southeastern South Korea and parts of northern Honshu.

Elsewhere over the Western North Pacific Ocean Tropical Depression 10W formed southeast of Guam.  At 11:00 p.m. EDT on Monday the center of Tropical Depression 10W was located at latitude 10.6°N and longitude 145.7°E which put it about 205 miles (330 km) south-southeast of Guam.  It was moving toward the north-northwest at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1003 mb.  A Tropical Storm Warning was issued for Guam.  A Tropical Storm Watch was issued for Tinian and Saipan.

Typhoon Prapiroon Brings Winds and Rain to Okinawa

Typhoon Prapiroon brought wind and rain to Okinawa on Sunday.  At 5:00 p.m. EDT on Sunday the center of Typhoon Prapiroon was located at latitude 26.8°N and longitude 126.8°E which put it about 65 miles (100 km) west-southwest of Okinawa.  Prapiroon was moving toward the north at 10 m.p.h. (16 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 978 mb.

The circulation of former Tropical Storm Prapiroon became much more well organized on Sunday.  A circular eye formed at the center of circulation and Prapiroon strengthened into a typhoon.  A ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms in the eastern half of the typhoon were revolving around the center of circulation.  Bands northwest of the center consisted mostly of showers and low clouds.  Storms in the core of the circulation were generating upper level divergence which was pumping mass away to the east of the typhoon.

Typhoon Prapiroon will move through an environment favorable for intensification during the next 12 to 24 hours.  Prapiroon will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Prapiroon could intensify during the next 12 to 24 hours.  Prapiroon will move over cooler water in a day or so.  It will also reach a location where an upper level trough west of South Korea will cause more vertical wind shear.  An environment of cooler water and more wind shear will cause Typhoon Prapiroon to weaken at that time.

Typhoon Prapiroon is moving around the western end of a subtropical ridge which is steering it toward the north.  On its anticipated track the center of Typhoon Prapiroon will pass west of Okinawa and the northern Ryukyu Islands.  Winds to typhoon force extend out about 30 miles (50 km) east of the center of circulation.  Winds to tropical storm force extend out about 150 miles (240 km) east of the center.  So, even though the center of Typhoon Prapiroon will pass west of the northern Ryukyu Islands, it will bring gusty winds and heavy rain.  Typhoon Prapiroon could approach western Kyushu in 24 hours.  When Prapiroon moves farther north the trough west of South Korea will start to steer the typhoon more toward the northeast.

Tropical Storm Prapiroon Moves Toward Okinawa

Tropical Storm Prapiroon moved closer to Okinawa on Saturday.  At 11:00 a.m. EDT on Saturday the center of Tropical Storm Prapiroon was located at latitude 22.4°N and longitude 128.3°E which put it about 315 miles (510 km) south of Okinawa.  Prapiroon was moving toward the northwest at 8 m.p.h. (13 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 992 mb.

There was a distinct center of circulation in the middle of Tropical Storm Prapiroon, but the distribution of thunderstorms was asymmetrical.  The stronger thunderstorms were occurring in bands south and east of the center of circulation.  The bands north and west of the center consisted primarily of showers and low clouds.  A large upper level ridge over Asia was producing northerly winds which were blowing toward the top of Tropical Storm Prapiroon.  Those winds were causing moderate vertical wind shear and they were probably the reason for the asymmetric distribution of thunderstorms.  Those winds were also blocking upper level divergence to the north and west of Prapiroon.

Tropical Storm Prapiroon will move through an area marginally favorable for intensification during the next 24 to 36 hours.  Prapiroon will move over water where the Sea Surface Temperature is near 29°C.  So, there will be enough energy in the upper ocean to support intensification.  The upper level ridge will continue to cause some vertical wind shear, but Tropical Storm Prapiroon could move into an area where the upper level winds are a little weaker on Sunday.  If the wind shear decreases, then Tropical Storm Prapiroon will intensify.  There is still a chance that Prapiroon could strengthen into a typhoon when it passes near Okinawa.

Tropical Storm Prapiroon is moving around the western end of a subtropical ridge over the Pacific Ocean which is steering the tropical storm toward the northwest.  Prapiroon is forecast to move more toward the north when it reaches the western end of the ridge in 12 to 24 hours.  On its anticipated track the center of Tropical Storm Prapiroon could approach Okinawa in 12 to 18 hours.  The center of Prapiroon will likely pass west of Okinawa which would bring the strongest winds and heaviest rain over Okinawa.

Tropical Storm Prapiroon Forms South-Southeast of Okinawa

A distinct center of circulation formed within an area of thunderstorms south-southeast of Okinawa on Thursday night and the Japan Meteorological Agency designated the system as Tropical Storm Prapiroon.  At 8:00 p.m. EDT on Thursday the center of Tropical Storm Prapiroon was located at latitude 20.0°N and longitude 130.2°E which put it about 500 miles (800 km) south-southeast of Okinawa.  Prapiroon was moving toward the west at 7 m.p.h. (11 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.

The circulation of Tropical Storm Prapiroon was still organizing.  More thunderstorms were forming close to the center of circulation.  There were more thunderstorms west of the center than there were east of the center.  Several bands of showers and thunderstorms in the outer part of the circulation were revolving around the core of Tropical Storm Prapiroon.  The storms in the core were generating upper level divergence which was pumping mass away from the tropical storm.

Tropical Storm Prapiroon formed beneath an upper level ridge that developed between an upper level low northwest of the Philippines and a much larger upper low east of the Marianas.  The winds in the upper ridge will be weak and there will be little vertical wind shear.  Prapiroon will move over water where the Sea Surface Temperature is near 29°C.  Tropical Storm Prapiroon will move through an environment very favorable for intensification.  Prapiroon will strengthen and it could intensify rapidly once the inner core organizes.  Tropical Storm Prapiroon could strengthen into a typhoon in 24 to 48 hours.

Tropical Storm Prapiroon was moving around the southwestern part of a subtropical ridge which was steering the tropical storm toward the west.  Prapiroon will turn toward the north in 12 to 24 hours when it reaches the western end of the ridge.  On its anticipated track Tropical Storm Prapiroon could approach Okinawa in about 36 hours.  Prapiroon could be a typhoon when it nears Okinawa.