Tag Archives: Iwo To

Large Powerful Typhoon Hagibis Turns Toward Japan

Large powerful Typhoon Hagibis turned toward Japan on Tuesday.  At 11:00 p.m. EDT on Tuesday the center of Typhoon Hagibis was located at latitude 20.2°N and longitude 140.1°E which put it about 350 miles (565 km) south of Iwo To.  Hagibis was moving toward the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 195 m.p.h. (315 km/h).  The minimum surface pressure was 915 mb.

Typhoon Hagibis appeared to complete an eyewall replacement cycle on Tuesday.  The original tiny pinhole eye was no longer visible on satellite imagery.  A larger circular eye with a diameter of 24 miles (39 km) was at the center of Hagibis.  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 Typhoon Hagibis.  Storms around the core were generating strong upper level divergence which was pumping mass away from the typhoon in all directions.

Completion of the eyewall replacement cycle increased the size of the circulation around Typhoon Hagibis.  Winds to typhoon force extended out 115 miles (185 km) from the center of circulation.  Winds to tropical storm force extended out 350 miles (565 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Hagibis was 35.0.  The Hurricane Size Index (HSI) was 38.1 and the Hurricane Wind Intensity Size Index (HWISI) was 73.1.  Hagibis was capable of causing extensive catastrophic damage.

Typhoon Hagibis will move through an environment capable of supporting intense typhoons during the next 24 to 36 hours.  Hagibis will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Hagibis will move closer to the upper level westerly winds in the middle latitudes in two or three days.  Those winds will cause more vertical wind shear and Hagibis will weaken when the shear increases.

Typhoon Hagibis will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean.  The high will steer Hagibis toward the north-northwest during the next 48 hours.  The upper level westerly winds will steer Typhoon Hagibis quickly toward the northeast later this week.  On its anticipated track the center of Typhoon Hagibis could approach the coast of Honshu near Tokyo in 72 to 84 hours.  Hagibis could bring strong winds and heavy rain to Tokyo.  The large circulation around Typhoon Hagibis will mean that much of central Honshu could experience gusty winds and winds to tropical storm force could affect parts of Kyushu and Shikoku.

Typhoon Lingling Speeds Toward Korea

Typhoon Lingling sped toward the Korean peninsula on Friday.  At 5:00 p.m. EDT on Friday the center of Typhoon Lingling was located at latitude 34.8°N and longitude 125.0°E which put it about 100 miles (160 km) west of Mokpo, South Korea.  Lingling was moving toward the north at 30 m.p.h. (48 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and thee were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 955 mb.

Typhoon Lingling was weakening gradually while it was speeding toward the north.  Lingling was moving over water where the Sea Surface Temperature was near 26°C.  An upper level trough over eastern Asia was producing strong southerly winds which blowing toward the top of the typhoon.  Those winds were causing moderate vertical wind shear.  The circulation around Typhoon Lingling was also pulling in drier air from Asia around the southern side of the circulation.  Even though it was weakening, Lingling remained a dangerous typhoon.  Winds to typhoon force extended out about 45 miles (75 km) from the center of circulation.  The stronger winds were primarily in the eastern half of the circulation.  Winds to tropical storm force extended out about 220 miles (350 km) from the center.

The upper trough over eastern Asia was steering Typhoon Lingling rapidly toward the north.  On its anticipated track Typhoon Lingling could reach the west coast of North Korea in less than 12 hours.  Lingling will be capable of causing serious damage.  It will also drop locally heavy rain over the Korean peninsula which could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, former Tropical Storm Faxai strengthened into a typhoon east of iwo To.  At 5:00 p.m. EDT on Friday the center of Typhoon Faxai was located at latitude 26.1°N and longitude 145.6°E which put it about 325 miles (520 km) east of Iwo To.  Faxai was moving toward the west-northwest at 21 m.p.h. (34 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.  Typhoon Faxai is forecast to move toward the northwest and strengthen.  Faxai could intensify into the equivalent of a major hurricane.  Typhoon Faxi could approach the area around Tokyo, Japan in less than 72 hours.

Tropical Storm Krosa Moves Toward Japan

Tropical Storm Krosa moved toward Japan on Sunday after stalling south of Iwo To for several days.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Krosa was located at latitude 24.7°N and longitude 137.5°E which put it about 255 miles (410 km) west of Iwo To.  Krosa was moving toward the west-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 965 mb.

Tropical Storm Krosa mixed significant amounts of cooler water to the surface during the days when it was nearly stationary south of Iwo To.  The cooler ware contained less energy and the atmosphere became more stable.  Thunderstorms around the core of the circulation dissipated and the storms in many of the rainbands also weakened.  Some thunderstorms persisted in outer rainbands.  Even though the maximum wind speed decreased, the size of the circulation increased.  Winds to tropical storm force extended out about 280 miles (455 km) from the center of circulation.

Tropical Storm Krosa will move through an environment favorable for intensification during the next several days.  Krosa will move over water where the Sea Surface Temperature is near 29°C after it gets away from the cooler water mixed to the surface.  It will move through a region where there will not be a lot of vertical wind shear.  Tropical Storm Krosa will intensify slowly at first because it lacks a strong inner core.  If more thunderstorms develop near the center of circulation, then Krosa could strengthen more quickly.  It is possible that thunderstorms do not form at  the center of circulation and if that happens, Krosa could develop into a typhoon with a very large eye at the center.

Tropical Storm Krosa will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Krosa toward the northwest during the next two or three days.  On its anticipated track Tropical Storm Krosa could approach southwestern Japan within 72 hours.  Krosa is likely to be a large typhoon by that time.

Elsewhere of over the Western North Pacific Ocean, Tropical Storm Lekima continue to bring wind and rain to parts of northeastern China.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Lekima was located at latitude 37.8°N and longitude 119.6°E which put it about 150 miles (240 km) south-southeast of Tangshan, China.  Lekima was moving toward the north- northwest at 12 m.p.h. (19 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 985 mb.

Damaging Tropical Storm Lekima Moves Up East Coast of China

Damaging Tropical Storm Lekima moved up the east coast of China on Saturday.  Although former Typhoon Lekima weakened to a tropical storm, there were reports that it caused deaths, damage and floods in eastern China.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Lekima was located at latitude 34.3°N and longitude 120.5°E which put it about 100 miles (160 km) south of Qingdao, China.  Lekima was moving toward the north at 18 m.p.h. (29 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 980 mb.

Former Typhoon Lekima made landfall south of Shanghai and then it moved northward over eastern China.  Lekima dropped heavy rain over areas near the east coast of China.  The heavy rain caused flooding in some locations.  Tropical Storm Lekima weakened on Saturday, but it continued to drop heavy rain on the coastal region north of Shanghai.  A portion of the circulation was still over the Yellow Sea and the strongest winds were occurring in rainbands over water.  Tropical Storm Lekima will continue to move northward and weaken on Sunday, but it still has the potential to cause additional flooding.

Elsewhere over the Western North Pacific Ocean, Typhoon Krosa finally started to move northwestward near Iwo To.  At 11:00 p.m. EDT on Saturday the center of Typhoon Krosa was located at latitude 23.2°N and longitude 139.9°E which put it about 140 miles (230 km) southwest of Iwo To.  Krosa was moving toward the northwest at 6 m.p.h. (10 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 965 mb.

Typhoon Krosa mixed cooler water to the surface while it was stationary south of Iwo To.  The cooler water didn’t provide enough energy to maintain the inner core of Krosa which weakened significantly.  Typhoon Krosa could strengthen when it moves away from the cooler water.  However, the lack of a well formed inner core will limit the rate of intensification.  Krosa will move around the western part of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer the typhoon toward the northwest.  On its anticipated track Typhoon Krosa could approach the large islands of Japan in about four days.

Typhoon Lekima Makes Landfall in China

Typhoon Lekima made landfall in China about 200 miles (320 km) south of Shanghai on Friday.  At 5:00 p.m. EDT on Friday the center of Typhoon Lekima was located at latitude 28.8°N and longitude 121.2°E which put it about 195 miles (315 km) south of Shanghai, China.  Lekima was moving toward the north-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h.  The minimum surface pressure was 960 mb.

The inner eye of Typhoon Lekima made landfall on the east coast of China in Zhejiang province about 200 miles (320 km) south of Shanghai on Friday.  Lekima was the the equivalent of a large, major hurricane at the time of landfall.  Winds to typhoon force extended out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extended out about 230 miles  (370 km) from the center.  Typhoon Lekima continued to exhibit two concentric eyewalls at the time of landfall.  The strongest winds were occurring around the small inner eye, but winds to typhoon force were also occurring in the large outer eyewall.  The double eyewall structure contributed to the large circulation around Lekima.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima a little to the west of due north.  On its anticipated track the center of Typhoon Lekima will remain inland, but it will also stay near the coast.  On its anticipated track the center of Typhoon Lekima will pass just to the west of Shanghai in 18 to 24 hours.  Lekima will weaken slowly while it moves northward.  The large size of the circulation and the fact that a portion of the circulation will remain over the Yellow Sea will lengthen the time it takes for the circulation to spin down.  Lekima is likely to be a tropical storm by the time the center nears Shanghai.  Typhoon Lekima will bring gusty winds and drop locally heavy rain over Zhejiang, Jiangsu and Shandong provinces.  Flash flooding is likely in places that receive prolonged heavy rain.

Elsewhere over the Western North Pacific Ocean, Typhoon Krosa remained stalled south of Iwo To.  At 5:00 p.m. EDT on Friday the center of Typhoon Krosa was located at latitude 22.4°N and longitude 141.3°E which put it about 175 miles (280 km) south of Iwo To.  Krosa was moving toward the north at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (170 km/h).  The minimum surface pressure was 975 mb.  Typhoon Krosa has been nearly stationary long enough to mix cooler water to the surface, which is why it weakened during the past 24 hours.  Krosa is forecast to move toward Iwo To during the next 24 to 36 hours.

Typhoon Lekima Moves Through Southern Ryukyu Islands

Powerful Typhoon Lekima moved through the southern Ryukyu Islands on Thursday.  At 5:00 p.m. EDT on Thursday the center of Typhoon Lekima was located at latitude 25.8°N and longitude 124.2°E which put it about 405 miles (655 km) south-southeast of Shanghai, China.  Lekima was moving toward the north-northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 165 m.p.h. (270 km/h).  The minimum surface pressure was 935 mb.

An inner rainband wrapped around the original eye and eyewall of Typhoon Lekima and a larger outer eye formed around the original eye.  The inner eye remained intact and the strongest winds were occurring in a small ring of thunderstorms around the inner eye.  The diameter of the outer eye was about 60 miles (95 km).  Additional bands of showers and thunderstorms were revolving around the two concentric eyewalls.

The formation of two concentric eyewalls increased the size of the circulation around Typhoon Lekima.  Winds to typhoon force extended out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 275 miles (445 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Lekima was 28.3.  The Hurricane Size Index (HSI) was 28.1 and the Hurricane Wind Intensity Size Index (HWISI) was 56.4.  Those indices indicated that Typhoon Lekima was capable of causing widespread significant damage.

The inner eye of Typhoon Lekima wobbled between Ishigakijima and Miyakojima on Thursday.  The inner eyewall appeared to pass over Taramajima and Minnajima.  No reports were available from a weather station on Taramajima.  Stations on Ishigakijima and Miyakojima reports winds to tropical storm force, but the strong inner eye passed between those two islands.

The formation of the larger outer eye probably indicates that an eyewall replacement cycle will occur.  Typhoon Lekima will weaken when the inner eyewall dissipates.  However, the circulation will remain large.  Typhoon Lekima will be in an environment favorable for strong typhoons during the next 24 hours.  Lekima will move over water where the Sea Surface Temperature is near 28.5°C.  It will move through a region where the upper level winds are not strong and there will not be a lot of vertical wind shear.  Typhoon Lekima will weaken because of an eyewall replacement cycle, but it will remain a large, powerful typhoon.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the north-northwest during the next several days.  On its anticipated track Typhoon Lekima could approach the coast of China south of Shanghai in about 24 hours.  It is likely to be a large typhoon at that time.

Elsewhere around the Western North Pacific Ocean, Typhoon Krosa was nearly stationary south of Iwo To on Thursday.  At 5:00 p.m. EDT on Thursday the center of Typhoon Krosa was located at latitude 22.1°N and longitude 141.0°E which put it about 195 miles (315 km) south of Iwo To.  Krosa was nearly stationary.  The maximum sustained wind speed was 110 m.p.h. (180 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 950 mb.

The circulation around Typhoon Krosa was also large.  Winds to typhoon force extended out about 75 miles (120 km) from the center of circulation.  Winds to tropical storm force extended out about 250 miles (405 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Krosa was 19.2.  The Hurricane Size Index (HSI) was 28.4 and the Hurricane Wind Intensity Size Index (HWISI) was 47.6.

Typhoon Krosa is forecast to move slowly north toward Iwo To on Friday.  On its anticipated track Krosa could approach Iwo To in about 36 hours.  It will be a large typhoon capable of causing serious damage at that time.

Typhoons Lekima and Krosa Threaten Japanese Islands

Typhoons Lekima and Krosa threatened Japanese islands on Wednesday.  Typhoon Lekima posed a serious threat to the southern Ryukyu Islands and Typhoon Krosa was headed for Iwo To.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Lekima was located at latitude 22.4°N and longitude 126.0°E which put it about 190 miles (305 km) southeast of Ishigaki, Japan.  Lekmia was moving toward the northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 925 mb.

Typhoon Lekima rapidly intensified into the equivalent of a major hurricane on Wednesday.  A small distinct eye was at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of the circulation.  Storms near the core were generating strong upper level divergence which was pumping mass away from the typhoon in all directions.

Typhoon Lekima had a large circulation.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Lekima was 23.6.  The Hurricane Size Index (HSI) was 21.6 and the Hurricane Wind Intensity Size Index (HWISI) was 44.7.   Those indices indicated that Typhoon Lekima was capable of causing widespread major damage.

Typhoon Lekima will move through an environment favorable for intensification during the next 24 hours.  Lekima will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will not be a lot of vertical wind shear.  Typhoon Lekima could intensify further during the next day or so.  It is possible that a rainband could wrap around the existing eye and eyewall.  If a rainband wraps around the core of Lekima then an eyewall replacement cycle could cause weakening.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the northwest on Thursday.  On its anticipated track Typhoon Lekima will reach Ishigaki and the southern Ryukyu Islands in less than 24 hours.  Lekima will be capable of causing major damage to the southern Ryukyu Islands.  Typhoon Lekima will move more toward the north when it moves around the end of the subtropical ridge.  The center of Lekima could be northeast of Taiwan within 36 hours.  Typhoon Lekima could reach the east coast of China in less than three days.

At 5:00 p.m. EDT on Wednesday the center of Typhoon Krosa was located at latitude 22.1°N and longitude 140.8°E which put it about 210 miles (340 km) south of Iwo To.  Krosa was moving toward the north-northwest at 5 m.p.h. (8 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 970 mb.

Former Tropical Storm Krosa strengthened into a typhoon on Wednesday.  The inner portion of a rainband wrapped around the center of circulation and an eye formed.  The inner part of the rainband closed around the eye and a circular ring of thunderstorms formed a closed eyewall.  The strongest winds were occurring in the eyewall.  Several bands of showers and thunderstorms were revolving around the core of Typhoon Krosa.  Storms near the center were pumping mass away to the east of the typhoon.

The circulation around Typhoon Krosa was also large.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 225 miles (360 km) from the center.  The Hurricane Intensity Index for Typhoon Krosa was 11.5.  The Hurricane Size Index was 22.5 and the Hurricane Wind Intensity Size Index was 34.0.

Typhoon Krosa will move through an environment mostly favorable for intensification.  Krosa will move over water where the Sea Surface Temperature is near 29°C.  Upper level divergence from Typhoon Lekima which is to the west of Typhoon Krosa could cause some vertical wind shear.  The wind shear will not be great enough to prevent intensification, but it could slow the rate at which Typhoon Krosa strengthens.

Typhoon Krose will move into a region where the steering winds are weaker.  Typhoon Krosa is forecast to move slowly toward the north during the next two or three days.  On its anticipated track the center of Typhoon Krosa could be near Iwo To in about 48 hours.

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.

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.