Typhoon Yutu Brings Wind and Rain to Luzon

Typhoon Yutu brought wind and rain to Luzon on Monday.  At 5:00 p.m. EDT on Monday the center of Typhoon Yutu was located at latitude 16.8°N and longitude 122.4°E which put it about 45 miles (75 km east of Ilagan, Philippines.  Yutu was moving toward the west at 14 m.p.h. (22 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. (200 km/h).  The minimum surface pressure was 949 mb.

The center of Typhoon Yutu made landfall near Palanan Point on the northeast coast of Luzon late on Monday.  Yutu had a large circulation.  Winds to typhoon force extended out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 270 miles (435 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Yutu was 17.8.  The Hurricane Size Index (HSI) was 25.5 and the Hurricane Wind Intensity Size Index (HWISI) was 43.3.  Typhoon Yutu is capable of causing widespread serious damage.

Typhoon Yutu could cause a storm surge of up to 10 feet (3 meters) on the northeast coast of Luzon.  It will also produce destructive winds as it moves across northern Luzon.  Yutu will move westward across Luzon.  It will move into the South China Sea south of Vigan, Philippines.  Typhoon Yutu will drop very heavy rain over parts of northern Luzon and flash flooding will be very likely.  Rapid runoff into the Cagayan River could cause it to flood.

Typhoon Yutu will move over the Sierra Madre mountains and the Cordillera Central when it moves across northern Luzon.  Those two mountain ranges will disrupt the lower levels of the circulation and Yutu will be weaker when it reaches the South China Sea.  Yutu could still be a typhoon when it moves back over water, but it may weaken to a tropical storm by then.

Typhoon Yutu will move around the western end of a ridge of high pressure over the Western North Pacific Ocean when it reaches the South China Sea.  Yutu will move toward the north when it reaches the western end of the ridge and it could approach China in four or five days.

Oscar Strengthens Into a Hurricane Southeast of Bermuda

One time subtropical storm and former Tropical Storm Oscar strengthened into a hurricane southeast of Bermuda on Sunday.  At 5:00 p.m. EDT on Sunday the center of Hurricane Oscar was located at latitude 25.7°N and longitude 55.5°W which put it about 725 miles (1165 km) southeast of Bermuda.  Oscar was moving toward the west at 16 m.p.h. (26 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 989 mb.

A small eye formed at the center of former Tropical Storm Oscar and the National Hurricane Center upgraded Oscar to a hurricane.  A thin ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several short bands of showers and thunderstorms were revolving around the core of Hurricane Oscar.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.

The circulation around Hurricane Oscar is relatively small.  Winds to hurricane force extend out only about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extend out about 115 miles (185 km) from the center.

Hurricane Oscar will move through an environment favorable for intensification for another day or two.  Oscar will move over water where the Sea Surface Temperature is near 27°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Because of its relatively small circulation, Hurricane Oscar could intensify rapidly while it is in a favorable environment.  Oscar will get stronger during the next 36 to 48 hours and some models are forecasting that it will become a major hurricane.  An upper level trough moving off the East Coast of the U.S. will produce southwesterly winds which will cause the vertical wind shear to increase by Wednesday.

Hurricane Oscar will move around the western end of a ridge of high pressure over the Atlantic Ocean on Monday and Tuesday.  The ridge will steer Oscar toward the west for another 12 to 24 hours.  Hurricane Oscar will move more toward the north when it reaches the western end of the ridge.  On its anticipated track Hurricane Oscar will pass east of Bermuda on Tuesday.  The upper level trough will steer Oscar rapidly toward the northeast on Wednesday.

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.

Oscar Transitions to a Tropical Storm

Former Subtropical Storm Oscar transitioned to a tropical storm on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Oscar was located at latitude 25.7°N and longitude 51.4°W which put it about 930 miles (1495 km) east-southeast of Bermuda.  Oscar was moving toward the west-southwest at 20 m.p.h. (32 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 994 mb.

The structure of the circulation of former Subtropical Storm Oscar changed to a shape more like a tropical cyclone and the National Hurricane Center reclassified Oscar as a tropical storm.  A band of showers and thunderstorms wrapped more tightly around the eastern side of the center of circulation.  The strongest winds were occurring about 30 miles (50 km) from the center.  Other bands of showers and thunderstorms were starting to form in the eastern half of the circulation.

Tropical Storm Oscar will move through an environment somewhat favorable for intensification during the next 36 hours.  Oscar will move over water where the Sea Surface Temperature is near 27°C.  An upper level low southeast of Oscar will produce northerly winds which will blow toward the top of the tropical storm.  However, the core of Tropical Storm Oscar will remain south of the strongest upper level winds on Sunday.  Tropical Storm Oscar could intensify into a hurricane by Monday.

The upper level low is steering Tropical Storm Oscar quickly toward the west-southwest.  That motion is forecast to continue for anther 24 hours.  A large upper level trough over the eastern U.S.  will produce southwesterly winds which will start to turn Oscar toward the northeast in about 36 to 48 hours.  On its anticipated track Tropical Storm Oscar could be southeast of Bermuda on Monday night.

Subtropical Storm Oscar Develops East of Bermuda

Subtropical Storm Oscar developed east of Bermuda on Friday night.  At 11:00 p.m. EDT on Friday the center of Subtropical Storm Oscar was located at latitude 26.7°N and longitude 45.7°W which put it about 1210 miles (1940 km) east-southeast of Bermuda.  Oscar was moving toward the north-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gust to 60 m.p.h. (95 km/h).  The minimum surface temperature was 1005 mb.

More thunderstorms developed closer to the center of a low pressure system east-southeast of Bermuda on Friday night and the National Hurricane Center designated the system as Subtropical Storm Oscar.  The strongest winds were occurring in a band of showers and thunderstorms about 80 to 100 miles (130 to 160 km) east of the center of the low pressure system.  Several other bands were forming southeast of the center of circulation.  Bands in other parts of Subtropical Storm Oscar consisted primarily of showers and low clouds.

Subtropical Storm Oscar will move through an area somewhat favorable for intensification.  Oscar will move over water where the Sea Surface Temperature is near 27°C.  An upper level low will move just to the south of Subtropical Storm Oscar.  The upper level low will produce easterly winds which will blow toward the top of the subtropical storm.  Those winds will cause moderate vertical wind shear which will inhibit intensification on Saturday.  In a day or so Oscar will move northwest of the upper level low and the vertical wind shear will decrease.

The upper level low will steer Subtropical Storm Oscar toward the north-northwest on Saturday.  When Oscar moves farther way from the upper level low, it will move south of a ridge of high pressure over the Atlantic Ocean.  The ridge will steer Subtropical Storm Oscar toward the west on Sunday and into early next week.  On its anticipated track Subtropical Storm Oscar could be southeast of Bermuda by Monday night.

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.

Major Hurricane Willa Makes Landfall in Mexico

Major Hurricane Willa made landfall on the coast of Mexico between Teacapan and Mazatlan on Tuesday evening.  At 8:00 p.m. EDT on Tuesday the center of Hurricane Willa was located at latitude 22.6°N and longitude 106.0°W which put it about 50 miles (80 km) south-southeast of Mazatlan, Mexico.  Willa was moving toward the north-northeast at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (220 km/h).  The minimum surface pressure was 965 mb.

A Hurricane Warning is in effect for the portion of the coast from San Blas to Mazatlan, Mexico.  Tropical Storm Warnings were in effect for the portions of the coast from Playa Perula to San Blas and from Mazatlan to Bahia Tempehuaya, Mexico.

An eyewall replacement cycle occurred in the core of Hurricane Willa on Tuesday.  When the original inner eyewall dissipated, the core of Willa was larger even though the maximum sustained wind speed was slower.  Winds to hurricane force extend out about 35 miles from the the center of Hurricane Willa.  Winds to tropical storm force extend out about 100 miles from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Willa is 22.1.  The Hurricane Size Index (HSI) is 12.7 and the Hurricane Wind Intensity Size Index (HWISI) s 34.8.  Hurricane Willa is capable of causing regional major damage.

Hurricane Willa will produce hurricane force winds along the coast between Tecuala and Mazatlan.  Those winds will be capable of causing major damage.  The winds will also push water toward the coast and a storm surge of 10 to 12 feet (3 to 4 meters) is possible.  Hurricane Willa will dissipate fairly quickly when it moves over the Sierra Madre Occidental Mountains.  However, Willa will drop locally heavy rain over the southern part of Sinaloa and over Durango.  The locally heavy rain is likely to cause flash floods in some locations.

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.