Tag Archives: Ryukyu Islands

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 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 Danas Nears Southern Ryukyu Islands

Tropical Storm Danas moved near the southern Ryukyu Islands late on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Danas was located at latitude 23.9°N and longitude 124.1°E which put it about 30 miles (50 km) south of Ishigaki, Japan.  Danas was moving toward the north at 21 m.p.h. (34 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 Danas exhibited a little more organization on Wednesday.  More thunderstorms formed near the center of circulation and several bands of showers and thunderstorms formed in the eastern half of the circulation.  The bands north and west of the center consisted primarily of showers and lower clouds.  Storms near the center began to generate upper level divergence which pumped mass away to the northeast of the tropical storm.  Winds to tropical storm force extended out about 125 miles (200 km) from the center of circulation.

Tropical Storm Danas will move into an environment somewhat favorable for intensification.  Danas will move over water where the Sea Surface Temperature is near 30°C.  A small upper level low near Taiwan will produce southwesterly winds which blow toward the top of the circulation around Tropical Storm Danas.  Those winds were the reason why the stronger rainbands were in the eastern half of the circulation.  Those winds will cause moderate vertical wind shear, which will inhibit intensification.  However, the shear will have less of an effect since Danas will move in the same direction as the upper level winds.  Tropical Storm Danas is likely to intensify during the next 24 hours and there is a chance it could strengthen into a typhoon.

Tropical Storm Danas will move around the western end of a subtropical ridge over the western North Pacific Ocean.  The ridge will steer Danas toward the north-northeast.  On its anticipated track Tropical Storm Danas will move through the southern Ryukyu Islands during the next few hours.  Danas will bring gusty winds and locally heavy rain when it passes over those islands.  Tropical Storm Danas will move over the East China Sea toward southwestern Japan and South Korea during the next several days.

Powerful Typhoon Yutu Threatens Northern Luzon

Powerful Typhoon Yutu continued to pose a threat to northern Luzon on Saturday.  At 11:00 p.m. EDT on Saturday the center of Typhoon Yutu was located at latitude 18.0°N and longitude 129.6°E which put it about 475 miles (765 km) east of Cape Engano, Philippines.  Yutu was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h).  The minimum surface pressure was 929 mb.

There were minor fluctuations in its intensity on Saturday, but Typhoon Yutu remains a very powerful tropical cyclone.  A circular eye is at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms.  Several bands of showers and thunderstorms are revolving around the core of Typhoon Yutu.  Storms around the core are generating strong upper level divergence which is pumping mass away from the typhoon in all directions.

Typhoon Yutu has a large circulation.  Winds to typhoon force extend out about 75 miles (120 km) from the center of circulation.  Winds to tropical storm force extend out about 250 miles (400 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Yutu is 31.6.  The Hurricane Size Index (HSI) is 28.3 and the Hurricane Wind Intensity Size Index (HWISI) is 59.9.  Typhoon Yutu is capable of causing wide spread significant damage.

Typhoon Yutu will continue to move south of a ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Yutu in a generally westerly direction for another 36 to 48 hours.  On its anticipated track Typhoon Yutu will reach northern Luzon in about 36 to 42 hours.  Yutu will create a storm surge at the coast.  It will cause significant wind damage over northern Luzon.  Yutu will also drop locally heavy rain and cause flash floods over parts of northern Luzon.

Powerful Typhoon Yutu Churns Toward Northern Luzon

Powerful Typhoon Yutu churned toward northern Luzon on Friday.  At 5:00 p.m. EDT on Friday the center of Typhoon Yutu was located at latitude 17.7°N and longitude 135.9°E which put it about 900 miles (1450 km) east of Cape Engano, Philippines.  Yutu was moving toward the west-northwest at 17 m.p.h. (28 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 920 mb.

After completing an eyewall replacement cycle Typhoon Yutu strengthened again on Friday.  Yutu is once again the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  The eyewall replacement cycle also caused an increase in the size of Typhoon Yutu’s circulation.  Winds to typhoon force extend out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extend out about 260 miles (420 km) from the center.  The Hurricane Intensity Index (HII) is 35.0.  The Hurricane Size Index (HSI) is 28.9 and the Hurricane Wind Intensity Size Index (HWISI) is 63.9.

Typhoon Yutu has a large, very well organized circulation and it will remain in an environment capable of supporting a powerful typhoon for several more days.  Yutu will move over water where the Sea Surface Temperature is near 31°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Yutu could strengthen a little more during the next 12 to 24 hours.  At some point another rainband is likely to wrap around the existing eye and eyewall, and another eyewall replacement cycle could occur.  If there is another eyewall replacement cycle, then Yutu would weaken, at least temporarily.

Typhoon Yutu will move south of a ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Yutu in a generally westward direction.  On its anticipated track Typhoon Yutu could reach northern Luzon in about four days.  Yutu is very likely to be a strong typhoon when it approaches Luzon.

Dangerous Typhoon Yutu Slams Tinian and Saipan

Dangerous Typhoon Yutu slammed Tinian and Saipan on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Yutu was located at latitude 15.5°N and longitude 144.8°E which put it about 35 miles (55 km) west-northwest of Saipan.  Yutu was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 205 m.p.h. (330 km/h).  The minimum surface pressure was 908 mb.

Typhoon Warnings were in effect for Rota, Tinian and Saipan.  Tropical Storm Warnings were in effect for Guam, Alamagan, Pagan and Agrihan.

The eye of Typhoon Yutu passed directly over Tinian on Wednesday and the northern side of the eyewall moved over Saipan.  So, they would have experienced the strongest parts of Typhoon Yutu.  The Hurricane Intensity Index (HII) for Typhoon Yutu is 40.4.  The Hurricane Size Index (HSI) is 26.7 and the Hurricane Wind Intensity Size Index (HWISI) is 67.1.  Typhoon Yutu was capable of causing widespread catastrophic damage when it passed over Tinian and Saipan.

Yutu is still a very powerful typhoon, but an eyewall replacement cycle appears to have started.  A rainband has wrapped around the original eye and eyewall.  The inner eye and eyewall are still intact and the strongest winds are occurring in the ring of thunderstorms that surround the original eye.  The imminent formation of a second, outer eyewall increased the size of the circulation around Typhoon Yutu.  Winds to typhoon force extend out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extend out about 240 miles (390 km) from the center.

Typhoon Yutu will remain in an environment capable of supporting a very strong typhoon for several more days.  Yutu will move over water where the Sea Surface Temperature is near 31°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  The incipient eyewall replacement cycle will cause Typhoon Yutu to weaken when the inner eyewall dissipates.  However, Yutu could strengthen again, if it remains in a favorable environment and the outer eyewall contracts closer to the center of circulation.  Typhoon Yutu is likely to remain a powerful typhoon during the next 48 hours.

Typhoon Yutu will move southwest of a ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Yutu toward the west-northwest during the next several days.  On its anticipated track Typhoon Yutu will move away from the Northern Marianas, and conditions should gradually improve there.  Yutu could be south of Okinawa in four or five days.

Typhoon Yutu Intensifies Rapidly to Equivalent of Cat. 4 Hurricane, Imminent Threat to Marianas

Typhoon Yutu intensified rapidly on Tuesday into the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale and Yutu posed an imminent threat to the Marianas.  At 11:00 p.m. EDT on Tuesday the center of Typhoon Yutu was located at latitude 13.6°N and longitude 147.5°E which put it about 155 miles (255 km) east-southeast of Rota.  Yutu was moving toward the northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h).  The minimum surface pressure was 935 mb.

Typhoon Warnings are in effect for Rota, Saipan and Tinian.  Tropical Storm Warnings are in effect for Guam, Alamagan, Pagan and Agrihan.

Typhoon Yutu intensified rapidly during the past 24 hours.  A circular eye developed at the center of Yutu.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Numerous bands of showers and thunderstorms were revolving around the core of Typhoon Yutu.  Storms near the core were generating strong upper level divergence which was pumping mass away from the typhoon in all directions.  The removal of mass allowed the surface pressure to decrease rapidly.

Typhoon Yutu has a large circulation.  Winds to typhoon force extend out about 65 miles (105 km) from the center of circulation.  Winds to tropical storm force extend out about 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Yutu is 31.6.  The Hurricane Size Index (HSI) is 20.8 and the Hurricane Wind Intensity Size index (HWISI) is 52.4.  Typhoon Yutu is capable of causing widespread extensive damage.

Typhoon Yutu will move through an environment favorable for further intensification during the next several days.  Yutu will move over water where the Sea Surface Temperature is near 31°C.  It will move through a region where the upper level winds are weak and there is little vertical wind shear.  Typhoon Yutu could intensify into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  At some point a rainband will wrap around the existing eye and eyewall, and an eyewall replacement cycle will occur.  Yutu will weaken during the eyewall replacement cycle, but the typhoon could strengthen afterwards if it remains in an environment favorable for intensification.

Typhoon Yutu will move around the southwestern portion of a ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Yutu in a general west-northwesterly direction.  On its anticipated track Typhoon Yutu will reach the Northern Marianas in about 12 hours.  The core of Yutu will pass between Rota and Tinian.  Rota, Tinian and Saipan are likly to have winds to typhoon force.  Typhoon Yutu will be capable of causing extensive damage in those locations.  Guam, Alamagan, Pagan and Agrihan are likely to receive winds to tropical storm force.  Wind speeds will be stronger on the northern part of Guam and the damage potential is greater there than it is for the southern part of Guam.

Yutu Strengthens Into a Typhoon East of the Marianas

Former Tropical Storm Yutu strengthened into a typhoon east of the Marianas on Monday evening.  At 11:00 p.m. EDT on Monday the center of Typhoon Yutu was located at latitude 11.8°N and longitude 151.2°E which put it about 475 miles (770 km) east-southeast of Guam.  Yutu was moving toward the west-northwest at 14 m.p.h. (22 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 975 mb.

A Typhoon Warning was in effect for Tinian and Saipan.  A Tropical Storm Warning was in effect for Rota.  Tropical Storm Watches were in effect for Guam, Alamagan, Pagan and Agrihan.

The circulation around Typhoon Yutu became better organized on Monday.  An inner rainband wrapped around the northern and western sides of the center of circulation.  A partial eyewall appeared to be forming.  Several bands of showers and thunderstorms were revolving around the center of Typhoon Yutu.  The strongest thunderstorms were developing in the bands in the eastern half of the circulation.  There were thunderstorms in bands in the western side of Typhoon Yutu, but those bands consisted primarily of showers and lower clouds.  Winds to typhoon force extended out about 60 miles (95 km) from center center of circulation.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.

Typhoon Yutu will move through an environment favorable for intensification during the next two or three days.  Yutu will move over water where the Sea Surface Temperature is near 30°C.  It will move through an environment where the upper level winds are weak and there will be little vertical wind shear.  Yutu will continue to intensify and it could strengthen into the equivalent of a major hurricane in a day or two.

Typhoon Yutu will move around the southwestern portion of an ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Typhoon Yutu toward the west-northwest during the next few days.  On its anticipated track Typhoon Yutu will move over the Northern Marianas in about 36 to 48 hours.  Yutu will be a typhoon when it reaches the Marianas.  It will bring strong winds and it could be capable of causing major damage.