Monthly Archives: April 2021

Typhoon Surigae Spins East of the Philippines

Typhoon Surigae spun east of the Philippines on Sunday. At 5:00 p.m. EDT on Sunday the center of Typhoon Surigae was located at latitude 14.2°N and longitude 126.4°E which put it about 260 miles (420 km) east of Daet, Philippines. Surigae was moving toward the northwest at 6 m.p.h. (10 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. (275 km/h). The minimum surface pressure was 934 mb.

An eyewall replacement cycle was underway in the core of Typhoon Surigae and the typhoon was weakening. The inner part of a rainband wrapped around the original eye and eyewall and a much larger outer eyewall formed. The low level winds converged into the outer eyewall and the inner eyewall weakened. The fastest wind speeds were in the inner eyewall. So, the maximum wind speed decreased when the inner eyewall weakened. There were still remnants of the original inner eyewall inside the outer eyewall, but the strongest wind speeds were occurring in the outer eyewall.

Typhoon Surigae was still large and powerful. Winds to typhoon force extended out 60 miles (95 km) from the center of Surigae. Winds to tropical storm force extended out 195 miles (315 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Surigae was 28.3. The Hurricane Size Index (HSI) was 16.9 and the Hurricane Wind Intensity Size Index (HWISI) was 45.2.

Typhoon Surigae will move through an environment capable of supporting a powerful typhoon during the next 24 hours. Surigae will be over water where the Sea Surface Temperatures will be near 29°C. It will move under the western part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce southerly winds which will blow toward the top of the circulation. However, the winds at lower levels in the atmosphere will also blow from the south and there will be little vertical wind shear. Typhoon Surigae will likely weaken gradually as the eyewall replacement cycle is completed.

Typhoon Surigae will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean during the next 48 hours. The high will steer Surigae toward the north-northwest during the next 48 hours. After that time Typhoon Surigae will approach the westerly winds in the middle latitudes. Those winds will turn Surigae toward the northeast. On its anticipated track, the core Typhoon Surigae with the strongest winds will remain east of Luzon.

Typhoon Surigae Rapidly Intensifies to Equivalent of Cat. 5 Hurricane

Typhoon Surigae rapidly intensified to the equivalent of a Category 5 hurricane on the Saffir-Simspson Scale on Saturday. At 11:00 a.m. EDT on Saturday the center of Typhoon Surigae was located at latitude 12.3°N and longitude 128.8°E which put it about 275 miles (445 km) east-southeast of Laoang, Philippines. Surigae was moving toward the northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 180 m.p.h. (290 km/h) and there were wind gusts to 215 m.p.h. (345 km/h). The minimum surface pressure was 900 mb.

Typhoon Surigae continued to intensify rapidly on Saturday. There was a circular eye with a diameter of 20 miles (32 km) at the center of Surigae. 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 Surigae. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon in all directions.

Typhoon Surigae was a large and powerful typhoon. Winds to typhoon force extended out 65 miles (105 km) from the center of Surigae. Winds to tropical storm force extended out 215 miles (345 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Surigae was 42.2. The Hurricane Size Index (HSI) was 23.7 and the Hurricane Wind Intensity Size Index (HWISI) was 65.9.

Typhoon Surigae will move through an environment capable of supporting a powerful typhoon during the next 24 hours. Surigae will be over water where the Sea Surface Temperatures will be near 30°C. It will move under the western part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce southeasterly winds which will blow toward the top of the circulation. However, the winds at lower levels in the atmosphere will also blow from the southeast and there will be little vertical wind shear. Typhoon Surigae may have attained its maximum intensity even though it will move through a very favorable environment. If the inner end of a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause Surigae to weaken.

Typhoon Surigae will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean during the next several days. The high will steer Surigae toward the north-northwest during the next 24 hours. After that time Typhoon Surigae will move more toward the north. On its anticipated track the core Typhoon Surigae with the strongest winds is forecast to pass east of the Philippines.

Typhoon Surigae Rapidly Intensifies to Equivalent of Major Hurricane

Typhoon Surigae rapidly intensified to the equivalent of a major hurricane on Friday. At 5:00 p.m. EDT on Friday the center of Typhoon Surigae was located at latitude 10.3°N and longitude 131.6°E which put it about 220 miles (330 km) northwest of Palau. Surigae was moving toward the west-northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 944 mb.

Typhoon Surigae rapidly intensified on Friday as it moved farther away from Palau. A small circular eye was present 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. Bands of showers and thunderstorms were revolving around the core of Typhoon Surigae. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon in all directions. The removal of mass allowed the pressure to decrease rapidly.

The circulation around Typhoon Surigae increased in size on Friday. Winds to typhoon force extended out 50 miles (80 km) from the center of Surigae. Winds to tropical storm force extended out 180 miles (290 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Surigae was 25.1. The Hurricane Size Index (HSI) was 18.8 and the Hurricane Wind Intensity Size Index (HWISI) was 43.9. Surigae was a large, dangerous typhoon capable of causing major damage.

Typhoon Surigae will move through an environment favorable for intensification during the next 24 hours. Surigae will be over water where the Sea Surface Temperatures will be near 30°C. It will move under the southwestern part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds which will blow toward the top of the circulation. However, the winds at lower levels in the atmosphere will also blow from the east and there will be little vertical wind shear. Typhoon Surigae will likely continue to intensify during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause Surigae to weaken.

Typhoon Surigae will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean during the next several days. The high will steer Surigae toward the northwest during the next 24 hours. After that time Typhoon Surigae will move more toward the north when it moves around the western end of the high pressure system. On its anticipated track Typhoon Surigae could be east of the Philippines in 36 hours.

Surigae Strengthens to Typhoon North of Palau

Former Tropical Storm Surigae strengthened to a typhoon north of Palau on Thursday night. At 11:00 p.m. EDT on Thursday the center of Typhoon Surigae was located at latitude 8.9°N and longitude 134.2°E which put it about 50 miles (80 km) north of Palau. Surigae was moving toward the west-northwest at 7 m.p.h. (11 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. (165 km/h). The minimum surface pressure was 973 mb. A weather station at the international airport on Palau reported a sustained wind speed of 46 m.p.h. (74 km/h) and a wind gust of 74 m.p.h. (118 km/h). There were reports of trees down and of wind damage on Palau.

Typhoon Surigae was intensifying more rapidly on Thursday night. Microwave satellite images showed an eye forming at the center of Surigae. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. The strongest rainbands were still in the western half of Typhoon Surigae, but more thunderstorms were developing in bands in the eastern half of the circulation. Storms near the center of Surigae were producing strong upper level divergence that pumped mass away from the typhoon. Winds to typhoon force extended out 30 miles (50 km) from the center of Typhoon Surigae. Winds to tropical storm force extended out 160 miles (260 km) from the center.

Typhoon Surigae will move through an environment favorable for intensification during the next 48 hours. Surigae will be over water where the Sea Surface Temperatures will be near 30°C. It will move under the southwestern part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds which will blow toward the top of the circulation. However, the winds at lower levels in the atmosphere will also blow from the east and there will be little vertical wind shear. Typhoon Surigae will continue to intensify and it could strengthen rapidly once an inner core is fully formed. Surigae could intensify to the equivalent of a major hurricane in 24 hours.

Typhoon Surigae will move around the southwestern part of a subtropical high pressure system over the Western North Pacific Ocean during the next few days. The high will steer Surigae toward the west-northwest during the next two days. After that time Typhoon Surigae will move more toward the north when it moves around the western end of the high pressure system. On its anticipated track Typhoon Surigae could be east of the Philippines in 48 hours. Conditions on Palau will improve gradually on Friday when Surigae moves farther away.

Tropical Storm Surigae Strengthens Northeast of Palau

Tropical Storm Surigae strengthened northeast of Palau on Wednesday. At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Surigae was located at latitude 9.1°N and longitude 136.2°E which put it about 120 miles (195 km) west-southwest of Yap. Serigae was moving toward the west-northwest at 5 m.p.h. (8 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 988 mb.

The circulation around Tropical Storm Surigae strengthened on Wednesday, but the distribution of thunderstorms was still asymmetrical. The strongest thunderstorms were occurring in bands in the western half of Surigae. Bands in the eastern half of the circulation consisted primarily of showers and lower clouds. Thunderstorms west of the center of circulation generated upper level divergence that pumped mass away to the west of the tropical storm. Winds to tropical storm force extended out 140 miles (220 km) from the center of Tropical Cyclone Surigae.

Tropical Storm Surigae will move through an environment favorable for intensification during the next several days. Surigae will be over water where the Sea Surface Temperatures will be near 30°C. It will move under the southwestern part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds which will blow toward the top of the circulation. Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification. Tropical Storm Surigae will continue to intensify and it could strengthen to a typhoon within 24 hours.

Tropical Storm Surigae will move around the southwestern part of a subtropical high pressure system over the Western North Pacific Ocean during the next few days. The high will steer Surigae toward the west-northwest during the next few days. On its anticipated track Tropical Storm Surigae will pass north of Palau during the next 36 hours. Surigae could be east of the Philippines by late this week.

Tropical Storm Surigae Develops Southwest of Yap

Tropical Storm Surigae developed southwest of Yap on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Surigae was located at latitude 8.2°N and longitude 137.1°E which put it about 35 miles (55 km) west-southwest of Ngulu. Serigae was moving toward the northwest at 4 m.p.h. (6 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.

Former Tropical Depression 02W strengthened southwest of Yap on Tuesday and the Japan Meteorological Agency designated the system as Tropical Storm Surigae. The circulation around Tropical Storm Surigae exhibited more organization on satellite images. Thunderstorms developed near the center of circulation. More thunderstorms also formed in bands revolving around the center of Surigae. Storms near the center of circulation began to generate upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 50 miles (80 km) from the center.

Tropical Storm Surigae will be in an environment favorable for intensification during the next several days. Surigae will be over water where the Sea Surface Temperatures will be near 30°C. It will be under the axis of an upper level ridge over the Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. The circulation around Tropical Storm Surigae will continue to get better organized. Surigae will intensify and it could strengthen to a typhoon within 48 hours.

Tropical Storm Surigae will move around the southwestern part of a subtropical high pressure system over the Western North Pacific Ocean during the next few days. The high will steer Surigae toward the northwest during the next few days. On its anticipated track Tropical Storm Surigae will pass north of Palau. Bands on the eastern side of Tropical Storm Surigae could bring gusty winds and locally heavy rain to Yap. Persistent heavy rain could cause flash floods. Surigae could be east of the Philippines by late this week.

Tropical Depression Forms Southeast of Yap

A tropical depression formed southeast of Yap on Monday night. At 8:00 p.m. EDT on Monday the center of the tropical depression was located at latitude 7.1°N and longitude 139.9°E which put it about 200 miles (320 km) southeast of Yap. The tropical depression was nearly stationary. The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1006 mb.

An area of low pressure exhibited more organization on Monday night and the Japan Meteorological Agency designated the system as a tropical depression. The circulation around the tropical depression was in the early stages of organization. There was a broad center of low pressure, but there were not a lot of thunderstorms near the center of circulation. Many of the stronger thunderstorms were occurring in two bands on the periphery of the tropical depression. The strongest rainband was north of the broad center of the depression. Another strong rainband was on the southern periphery of the circulation.

The tropical depression will be in an environment favorable for intensification during the next several days. The depression will be over water where the Sea Surface Temperatures will be near 30°C. It will be under the center of an upper level ridge over the Western North Pacific Ocean. The upper level winds are weak in the center of the ridge and there will be little vertical wind shear. The circulation around the tropical depression is forecast to gradually get better organized and it could strengthen to a tropical storm during the next 24 hours. The depression is forecast to intensify into a typhoon later this week.

The tropical depression will be in an area where the steering winds are weak during the next several days. It will remain nearly stationary during that time period. A subtropical high pressure system over the Western North Pacific Ocean will begin to steer the tropical depression toward the northwest later this week. On its anticipated track the tropical depression will pass near Yap. It will bring gusty winds and locally heavy rain. Persistent heavy rain could cause flash floods.

Tropical Cyclone Seroja Brings Wind and Rain to Western Australia

Tropical Cyclone Seroja brought wind and rain to Western Australia on Sunday. At 8:00 a.m. EDT on Sunday the center of Tropical Cyclone Seroja was located at latitude 28.1°S and longitude 114.3°E which put it about 30 miles (45 km) south-southeast of Kalbarri, Australia. Seroja was moving toward the southeast at 26 m.p.h. (43 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 976 mb.

A Tropical Cyclone Warning was in effect from Overlander Roadhouse to Lancelin. The Warning extended inland to Merredin.

Tropical Cyclone Seroja made landfall on the coast of Western Australia between Kalbarri and Geraldton. Seroja strengthened to the equivalent of a hurricane/typhoon before it made landfall. The airport at Geraldton was reporting sustained winds to 56 m.p.h. (91 km/h) and wind gusts to 75 m.p.h. (120 km/h) as the center of Tropical Cyclone Seroja approached the station.

Tropical Cyclone Seroja will move rapidly across the southwestern part of Western Australia during the next 24 hours. Seroja will bring gusty winds and it will drop locally heavy rain over parts of Western Australia. Flood Watches have been issued for the Wooramel, Murchison, Greenough, Yarra Yarra Lakes, Avon River and parts of the Salt Lake Catchments.

Tropical Cyclone Seroja Turns Toward Western Australia

Tropical Cyclone Seroja turned toward the coast of Western Australia on Saturday. At 5:00 p.m. EDT on Saturday the center of Tropical Cyclone Seroja was located at latitude 23.2°S and longitude 110.2°E which put it about 435 miles (700 km) northwest of Kalbarri, Australia. Seroja was moving toward the southeast at 12 m.p.h. (19 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.

A Tropical Cyclone Warning was in effect from Minilya Roadhouse to Lancelin, Australia. The Warning included Cape Cuvier, Carnavon, Denham, Kalbarri, Jurien Bay and Lancelin.

Tropical Cyclone Seroja intensified to the equivalent of a hurricane/typhoon after it turned toward the coast of Western Australia on Saturday. The inner end of a rainband wrapped around the center of Seroja and microwave satellite images showed evidence of the formation of an eye. The strongest thunderstorms were occurring in bands in the eastern half of Tropical Cyclone Seroja. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Storms near the center of Seroja generated upper level divergence that pumped mass away to the southeast of the tropical cyclone. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Tropical Cyclone Seroja. Winds to tropical storm force extended out 125 miles (200 km) from the center of circulation.

Tropical Cyclone Seroja will move through an environment favorable for intensification during the next 12 hours. Seroja will move over water where the Sea Surface Temperatures will be near 29°C. An upper level trough over the South Indian Ocean will produce northwesterly winds which will blow toward the top of Seroja. Those winds will cause moderate vertical wind shear. The wind shear will limit intensification, but Tropical Cyclone Seroja could get a little stronger during the next 12 hours. Seroja will begin to weaken when it moves over Western Australia.

The upper level trough over the South Indian Ocean will steer Tropical Cyclone Seroja toward the southeast during the next 36 hours. On its anticipated track the center of Tropical Cyclone Seroja will pass just to the west of Denham during the next 12 hours. Seroja make landfall on the coast of Western Australia near Kalbarri in 15 hours. Tropical Cyclone Seroja will move across the southwestern part of Western Australia after it makes landfall.

Tropical Cyclone Seroja will bring produce winds to hurricane/typhoon force to the portion of the coast near Kalbarri. Winds to tropical storm force could occur along the portion of the coast from Denham to Geraldton. Wind blowing water toward the coast could cause a storm surge of up to 7 feet (2 meters) near where the center makes landfall. Tropical Cyclone Seroja will drop locally heavy rain over parts of Western Australia. Flood Watches have been issued for the Wooramel, Murchison, Greenough, Yarra Yarra Lakes, Avon River and parts of the Salt Lake Catchments.

Tropical Cyclone Seroja Prompts Watch for Western Australia

A potential threat posed by Tropical Cyclone Seroja prompted the issuance of a Watch for the coast of Western Australia. At 11:00 p.m. EDT on Thursday the center of Tropical Cyclone Seroja was located at latitude 19.2°S and longitude 109.8°E which put it about 315 miles (505 km) northwest of Exmouth, Australia. Seroja was moving toward the southwest at 12 m.p.h. (19 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 994 mb.

A Tropical Cyclone Watch was issued for the portion of the coast of Western Australia from Coral Bay to Lancelin. The Watch included Carnarvon, Denham, Kalbarri and Geraldton.

More thunderstorms developed in bands revolving around the center of Tropical Cyclone Seroja on Thursday night. The distribution of thunderstorms was more symmetrical, which indicated that the vertical wind shear was decreasing. Thunderstorms near the center of circulation generated upper level divergence that pumped mass away from the tropical cyclone. Winds to tropical storm force extended out 115 miles (185 km) from the center of Seroja.

Tropical Cyclone Seroja will move through an environment favorable for intensification during the next 36 hours. Seroja will move over water where the Sea Surface Temperatures will be near 30°C. It will move under the axis of an upper level ridge centered northwest of Australia during the next 24 hours. The upper level winds are weaker near the axis of the ridge and the wind shear will decrease. Tropical Cyclone Seroja could strengthen into the equivalent of a hurricane/typhoon during the next 24 hours. Seroja could strengthen more rapidly if the inner end of a rainband wraps around the center and an inner core forms.

Tropical Cyclone Seroja will move around the northwestern part of a high pressure system over Australia during the next day or so. The high will steer Seroja toward the southwest during the next 24 hours. An upper level trough over the South Indian Ocean will approach Tropical Cyclone Seroja from the west during the weekend. The trough will turn Seroja toward the southeast. On its anticipated track Tropical Cyclone Seroja will make landfall on the coast of Western Australia between Denham and Lancelin in 60 hours.

Elsewhere over the South Indian Ocean, Tropical Cyclone Odette was interacting with the northwest side of Tropical Cyclone Seroja. At 11:00 p.m. EDT on Thursday the center of Tropical Cyclone Odette was located at latitude 14.5°S and longitude 108.2°E which put it about 675 miles (1090 km) northwest of Exmouth, Australia. Odette was moving toward the east at 9 m.p.h. (15 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 988 mb. Even though the wind speeds are stronger in Tropical Cyclone Odette than they are in Tropical Cyclone Seroja, the circulation around Seroja is larger. The circulation of Odette is forecast to absorbed by the larger circulation of Seroja. In addition, upper level divergence from Seroja will cause vertical wind shear over Odette, which will also cause the circulation around Odette to weaken.