Monthly Archives: December 2021

Typhoon Rai Rapidly Intensifies to Equivalent of Cat. 5 Hurricane

Typhoon Rai rapidly intensified to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale on Wednesday night. At 10:00 p.m. EST on Wednesday the center of Typhoon Rai was located at latitude 9.8°N and longitude 126.3°E which put it about 90 miles (145 km) east of Dinagat, Philippines. Rai was moving toward the west at 16 m.p.h. (26 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 Rai continued to intensify very rapidly during Wednesday evening and it strengthened to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale. A small circular eye with a diameter of 8 miles (13 km) was at the center of Rai’s 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 Rai. Storms near the core of Rai generated strong upper level divergence that pumped large quantities of mass away to the west and north of the typhoon. The continued rapid removal of mass allowed the surface pressure to decrease very rapidly.

The circulation around Typhoon Rai exhibited more symmetry as it rapidly intensified. Winds to typhoon force extended out 50 miles (80 km) from the center of Rai. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Rai was 35.0. The Hurricane Size Index (HSI) was 17.5 and the Hurricane Wind Intensity Size Index (HWISI) was 52.5. Typhoon Rai was capable of doing regional catastrophic damage.

Typhoon Rai will move through an environment favorable for intensification during the next few hours. Rai will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the southern side of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Typhoon Rai’s circulation. Those winds will cause some vertical wind shear but the wind shear will be too small to prevent intensification. Typhoon Rai could continue to strengthen until the center makes landfall in southern Philippines in a few hours. Rai will weaken when the center passes over land.

Typhoon Rai will move south of a surface high pressure system over the Western North Pacific Ocean. The high pressure system will steer Rai toward the west-northwest during the next 36 hours. On its anticipated track the center of Typhoon Rai will pass over Siargao Island in a few hours. The core of Rai will pass over Dinagat Island, southern Leyte, northern Bohol, Cebu, northern Negros and southern Panay Island. Typhoon Rai will weaken when the center passes over land, but it will be the equivalent of a major hurricane when it moves across the southern Philippines. Typhoon Rai will bring very strong winds and locally heavy rain to northern Mindanao, Siargao Island, Dinagat Island, Samar, Leyte, Cebu, Negros, Bohol and Panay Island. Heavy rain could cause flash floods in some locations. Rai will cause a significant storm surge along coasts where the wind blows the water toward the shore. Typhoon Rai could cause catastrophic damage in locations that experience the inner core of the circulation.

Typhoon Rai Rapidly Intensifies to Equivalent of a Major Hurricane

Typhoon Rai rapidly intensified to the equivalent of a major hurricane on Wednesday. At 4:00 p.m. EST on Wednesday the center of Typhoon Rai was located at latitude 9.5°N and longitude 128.3°E which put it about 190 miles (305 km) east of Dinagat, Philippines. Rai was moving toward the west at 13 m.p.h. (20 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 942 mb.

Typhoon Rai intensified very rapidly during Wednesday afternoon and it reached the equivalent of a major hurricane. . A small circular eye with a diameter of 8 miles (13 km) was at the center of Rai’s 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 Rai. Storms near the core of Rai generated strong upper level divergence that pumped large quantities of mass away to the west and north of the typhoon. The removal of mass allowed the surface pressure to decrease rapidly.

The circulation around Typhoon Rai increased in size as it rapidly intensified. Winds to typhoon force extended out 45 miles (75 km) from the center of Rai. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Rai was 25.1. The Hurricane Size Index (HSI) was 17.1 and the Hurricane Wind Intensity Size Index (HWISI) was 42.2. Typhoon Rai was capable of doing regional severe damage.

Typhoon Rai will move through an environment favorable for intensification during the next 12 hours. Rai will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the southern side of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Typhoon Rai’s circulation. Those winds will cause some vertical wind shear but the wind shear will be too small to prevent intensification. Typhoon Rai will continue to strengthen during the next 12 hours. Rai could continue to rapidly intensify during the next few hours.

Typhoon Rai will move south of a surface high pressure system over the Western North Pacific Ocean. The high pressure system will steer Rai toward the west-northwest during the next 48 hours. On its anticipated track the center of Typhoon Rai could approach northern Mindanao in 12 hours. Rai will be the equivalent of a major hurricane when it reaches the Philippines. Typhoon Rai will bring very strong winds and locally heavy rain to northern Mindanao, Siargao Island, Dinagat Island, Samar, Leyte, Cebu, Negros, Bohol and Panay Island. Heavy rain could cause flash floods in some locations. Rai will cause a significant storm surge along coasts where the wind blows the water toward the shore.

Typhoon Rai Strengthens East of Mindanao

Typhoon Rai strengthened east of Mindanao on Wednesday morning. At 10:00 a.m. EST on Wednesday the center of Typhoon Rai was located at latitude 9.5°N and longitude 129.3°E which put it about 260 miles (415 km) east of Dinagat, Philippines. Rai was moving toward the west at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h). The minimum surface pressure was 969 mb.

Typhoon Rai continued to intensify during Tuesday night and Wednesday morning. A small circular eye was at the center of Rai’s 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 Rai. The strongest rainbands were in the western and southern parts of the typhoon. Storms near the core of Rai generated upper level divergence that pumped mass away to the west and north of the typhoon.

The circulation around Typhoon Rai tightened as it intensified. Winds to typhoon force extended out 40 miles (65 km) from the center of Rai. Winds to tropical storm force extended out 125 miles (200 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Rai was 13.9. The Hurricane Size Index (HSI) was 10.0 and the Hurricane Wind Intensity Size Index (HWISI) was 23.9. Typhoon Rai was capable of doing regional serious damage.

Typhoon Rai will move through an environment favorable for intensification during the next 18 hours. Rai will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the southern side of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Typhoon Rai’s circulation. Those winds will cause some vertical wind shear but the wind shear will be too small to prevent intensification. Typhoon Rai will continue to strengthen during the next 18 hours. Rai could undergo a period of rapid intensification

Typhoon Rai will move south of a surface high pressure system over the Western North Pacific Ocean. The high pressure system will steer Rai toward the west-northwest during the next 48 hours. On its anticipated track the center of Typhoon Rai could approach northern Mindanao in 18 hours. Rai will be a typhoon when it reaches the Philippines. Typhoon Rai will bring strong winds and locally heavy rain to northern Mindanao, Siargao Island, Dinagat Island, Samar, Leyte, Cebu, Negros, Bohol and Panay Island. Heavy rain could cause flash floods in some locations. Rai will cause a significant storm surge along coasts where the wind blows the water toward the shore.

Rai Intensifies to a Typhoon East of the Philippines

Former Tropical Storm Rai intensified to a typhoon east of the Philippines on Tuesday night. At 10:00 p.m. EST on Tuesday the center of Typhoon Rai was located at latitude 9.0°N and longitude 131.7°E which put it about 180 miles (290 km) northwest of Koror, Palau. Rai was moving toward the west 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 981 mb.

Former Tropical Storm Rai intensified steadily on Tuesday over the Western North Pacific Ocean and it reached typhoon intensity on Tuesday night. A small circular eye formed at the center of Rai. 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 Rai. Storms near the core generated upper level divergence that pumped mass away to the west and north of the typhoon. Winds to typhoon force extended out 45 miles (75 km) from the center of Rai’s circulation. Winds to tropical storm force extended out 180 miles (290 km) from the center.

Typhoon Rai will move through an environment favorable for intensification during the next 24 hours. Rai will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the southern side of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Typhoon Rai’s circulation. Those winds will cause some vertical wind shear but the wind shear will be too small to prevent intensification. Typhoon Rai will continue to strengthen. Rai could intensify more rapidly now that an inner core with an eye and an eyewall has formed.

Typhoon Rai will move south of a surface high pressure system over the Western North Pacific Ocean. The high pressure system will steer Rai toward the west-northwest during the next several days. On its anticipated track the center of Typhoon Rai could approach northern Mindanao in 24 hours. Rai will be a typhoon when it reaches the Philippines. Typhoon Rai will bring strong winds and locally heavy rain to northern Mindanao, Siargao Island, Dinegat Island, Samar, Leyte, Cebu, Negros, Bohol and Panay Island. Rai will cause a significant storm surge along coasts where the wind blows the water toward the shore.

Tropical Cyclone Ruby Brings Wind and Rain to New Caledonia

Tropical Cyclone Ruby brought wind and rain to New Caledonia on Monday night. At 4:00 a.m. EST on Tuesday the center of Tropical Cyclone Ruby was located at latitude 22.6°S and longitude 168.3°E which put it about 85 miles (135 km) east of Noumea, New Caledonia. Ruby was moving toward the east-southeast at 22 m.p.h. (35 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.

Tropical Cyclone Ruby brought wind and rain to much of New Caledonia on Monday night. The center of Ruby made landfall on the northwest end of New Caledonia near Poum. Tropical Cyclone Ruby moved quickly toward the southeast and the center of circulation passed over most of the entire length of New Caledonia. The center exited the coast east of Noumea on Tuesday morning. Winds to tropical storm force extended out 60 miles in the northern half of Ruby’s circulation. So, Tropical Cyclone Ruby brought tropical storm force winds to much of New Caledonia. The winds in the southern half of Ruby’s circulation were blowing at less than tropical storm force. Tropical Cyclone Ruby also dropped locally heavy rain over parts of New Caledonia. Clockwise rotation around Ruby would have caused the air to flow up the eastern slopes of mountains and the heaviest rain likely occurred in those areas. Locally heavy rain may have caused flash floods in some places.

An upper level trough east of Australia will steer Tropical Cyclone Ruby quickly toward the southeast during the next 36 hours. On its anticipated track Ruby will be northeast of New Zealand in 36 hours. The upper level trough will produce strong northwesterly winds that will blow toward the top of Ruby’s circulation. Those winds will produce moderate vertical wind shear. Tropical Cyclone Ruby will move over much cooler water when it moves toward the southeast. The combination of moderate vertical wind shear and cooler water will cause Tropical Cyclone Ruby to make a transition to an extratropical cyclone during the next 36 hours.

Tropical Storm Rai Strengthens East of Palau

Tropical Storm Rai strengthened east of Palau on Monday night. At 10:00 p.m. EST on Monday the center of Tropical Storm Rai was located at latitude 7.7°N and longitude 136.3°E which put it about 170 miles (275 km) east of Koror, Palau. Rai was moving toward the west-northwest at 21 m.p.h. (33 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 Rai strengthened steadily over the Western North Pacific Ocean on Monday. Although Rai intensified, the distribution of thunderstorms was asymmetrical. The strongest thunderstorms were occurring in bands in the western half of Tropical Storm Rai’s circulation. The inner end of a rainband wrapped around the western and southern side of the center of Rai’s circulation. Bands in the eastern half of the tropical storm consisted primarily of showers and lower clouds. Storms near the center of circulation generated upper level divergence that pumped mass away to the west and north of the tropical storm. Winds to tropical storm force extended out 200 miles (320 km) from the center of Rai.

Tropical Storm Rai will move through an environment favorable for intensification during the next 48 hours. Rai will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the southern side of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Tropical Storm Rai’s circulation. Those winds will cause some vertical wind shear and the shear is already contributing to the current asymmetrical distribution of thunderstorms. The upper level winds are forecast to weaken, and the vertical wind shear will be too small to prevent intensification. Tropical Storm Rai will intensify and it likely to strengthen to a typhoon during the next 24 hours. Rai could strengthen more rapidly once an inner core with an eye and an eyewall forms.

Tropical Storm Rai will move south of a surface high pressure system over the Western North Pacific Ocean. The high pressure system will steer Rai toward the west-northwest during the next several days. On its anticipated track the center of Tropical Storm Rai will north of Palau during the next 12 hours. Rai could bring gusty winds and locally heavy rain to Palau. Tropical Storm Rai could approach the Philippines in 60 hours. Rai is likely to be a typhoon when it reaches the Philippines.

Tropical Cyclone Ruby Hits New Caledonia

Tropical Cyclone Ruby hit New Caledonia on Monday. At 4:00 p.m. EST on Monday the center of Tropical Cyclone Ruby was located at latitude 20.5°S and longitude 164.5°E which put it about 20 miles (30 km) east of Koumac, New Caledonia and about 200 miles (320 km) northwest of Noumea. Ruby was moving toward the southeast at 18 m.p.h. (29 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 984 mb.

The center of Tropical Cyclone Ruby made landfall on the northwest end of New Caledonia near Poum on Monday. Ruby was the equivalent of a strong tropical storm when it made landfall. Winds to tropical storm force extended out 140 miles (225 km) in the northeastern quadrant of Ruby’s circulation. Winds to tropical storm force extended out 80 miles from the center of Tropical Cyclone Ruby in the other quadrants. A band of heavy rain wrapped around the southern and western sides of the center of circulation. Other bands of showers and thunderstorms were revolving around the center of Ruby.

An upper level trough east of Australia will produce northwesterly winds that will steer Tropical Cyclone Ruby toward the southeast during the next 36 hours. On its anticipated track the center of Ruby will move over almost the entire length of New Caledonia. Ruby could maintain much of its intensity as it moves over New Caledonia because most of the circulation will be over water. Tropical Cyclone Ruby will bring strong winds and heavy rain to much of New Caledonia. Locally heavy rain is likely to cause flash floods. Strong winds and locally heavy rain could cause widespread electrical outages. Winds blowing water toward the east coast of New Caledonia could cause storm surges.

Tropical Storm Rai Forms Southeast of Yap

Tropical Storm Rai formed over the Western North Pacific Ocean southeast of Yap on Monday morning. At 4:00 a.m. EST on Monday the center of Tropical Storm Rai was located at latitude 5.5°N and longitude 140.5°E which put it about 355 miles (575 km) southeast of Yap. Rai was moving toward the west-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.

The circulation around a low pressure system strengthened on Monday morning and the Japan Meteorological Agency designated the system as Tropical Storm Rai. Thunderstorms formed near the center of Tropical Storm Rai. More thunderstorms also developed in bands revolving around the center of Rai. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 150 miles (240 km) from the center of Tropical Storm Rai.

Tropical Storm Rai will move through an environment favorable for intensification during the next several days. Rai will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the southern side of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Tropical Storm Rai’s circulation. Those winds will cause some vertical wind shear, but the shear will be too small to prevent intensification. Tropical Storm Rai will intensify during the next several days. Rai could strengthen to a typhoon within 36 hours. It could strengthen more rapidly once an inner core with an eye and an eyewall forms.

Tropical Storm Rai will move south of a surface high pressure system over the Western North Pacific Ocean. The high pressure system will steer Rai toward the west-northwest during the next several days. On its anticipated track the center of Tropical Storm Rai will south of Yap during the next 24 hours. Rai could bring gusty winds and locally heavy rain to Yap. Tropical Storm Rai could affect Palau within 36 hours. Rai could approach the Philippines within 72 hours. Rai is likely to be a typhoon when it reaches the Philippines.

Tropical Cyclone Ruby Rapidly Intensifies to Equivalent of a Hurricane/Typhoon

Tropical Cyclone Ruby rapidly intensified to the equivalent of a hurricane/typhoon on Sunday afternoon. At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Ruby was located at latitude 16.8°S and longitude 159.3°E which put it about 415 miles (670 km) northwest of Poum, New Caledonia. Ruby 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 980 mb.

Tropical Cyclone Ruby rapidly intensified on Sunday. A small eye formed at the center of Ruby. 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 Tropical Cyclone Ruby’s circulation. Storms near the core generated upper level divergence that pumped mass away to the southeast of the tropical cyclone. Ruby was a small tropical cyclone. Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Ruby’s circulation. Winds to tropical storm force extended out 75 miles (120 km) from the center of circulation.

Tropical Cyclone Ruby will move through an environment favorable for intensification during the next 24 hours. Ruby will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western part of an upper level ridge over the South Pacific Ocean. The ridge will produce northwesterly winds that will blow toward the top of Ruby’s circulation. Those winds will cause some vertical wind shear, but the wind shear will be too small to prevent intensification. Tropical Cyclone Ruby will intensify and it could continue to intensify rapidly. Ruby could strengthen to the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale.

Tropical Cyclone Ruby will move around the southwestern part of a high pressure system over the South Pacific Ocean during the next 36 hours. The high pressure system will steer Ruby toward the southeast. On its anticipated track Tropical Cyclone Ruby could approach the northwestern part of New Caledonia in 24 hours. Ruby will be the equivalent of a hurricane/typhoon when it reaches New Caledonia. Tropical Cyclone Ruby will bring strong winds and heavy rain to much of New Caledonia. Locally heavy rain is likely to cause flash floods. Strong winds and locally heavy rain could cause widespread electrical outages. Winds blowing water toward the east coast of New Caledonia could cause storm surges.

Tropical Cyclone Ruby Intensifies over the Coral Sea

Tropical Cyclone Ruby intensified over the Coral Sea on Sunday morning. At 10:00 a.m. EST on Sunday the center of Tropical Cyclone Ruby was located at latitude 16.2°S and longitude 158.6°E which put it about 475 miles (765 km) northwest of Poum, New Caledonia. Ruby was moving toward the south-southeast at 13 m.p.h. (20 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 Cyclone Ruby intensified more rapidly over the Coral Sea northwest of New Caledonia on Sunday morning. Microwave satellite images provided evidence that a small eye was forming at the center of Ruby’s 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 Tropical Cyclone Ruby. Storms near the core generated upper level divergence that pumped mass away to the southeast of the tropical cyclone. The circulation around Ruby was small. Winds to tropical storm force extended out 70 miles from the center of circulation.

Tropical Cyclone Ruby will move through an environment favorable for intensification during the next 24 hours. Ruby will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western part of an upper level ridge over the South Pacific Ocean. The ridge will produce northwesterly winds that will blow toward the top of Ruby’s circulation. Those winds will cause some vertical wind shear, but the wind shear will be too small to prevent intensification. Tropical Cyclone Ruby will intensify and it could strengthen to the equivalent of a hurricane/typhoon within 12 hours.

Tropical Cyclone Ruby will move around the southwestern part of a high pressure system over the South Pacific Ocean during the next 36 hours. The high pressure system will steer Ruby toward the southeast. On its anticipated track Tropical Cyclone Ruby could approach the northwestern part of New Caledonia in 36 hours. Ruby is very likely to be the equivalent of a hurricane/typhoon when it nears New Caledonia. Tropical Cyclone Ruby will bring strong winds and heavy rain to much of New Caledonia. Locally heavy rain is likely to cause widespread flash floods.