Category Archives: Tropical Cyclones

Information about tropical cyclones

Powerful Typhoon Doksuri Moves Near Northern Luzon

Powerful Typhoon Doksuri moved near northern Luzon on Monday night. At 11:00 p.m. EDT on Monday the center of Typhoon Doksuri was located at latitude 17.9°N and longitude 124.2°E which put it about 165 miles (265 km) east-southeast of Aparri, Philippines. Doksuri was moving toward the northwest at 9 m.p.h. (15 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 926 mb.

Typhoon Doksuri strengthened to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Monday as it moved over the Western North Pacific Ocean just to the east of northern Luzon. A circular eye with a diameter of 40 miles (65 km) was present at the center of Doksuri’s circulation. The eye was surrounded with 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 Doksuri. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon.

Doksuri was a large typhoon. Winds to typhoon force extended out 80 miles (130 km) from the center of Doksuri’s circulation. Winds to tropical storm force extended out 295 miles (475 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Doksuri was 31.6. The Hurricane Size Index (HSI) was 28.8 and the Hurricane Wind Intensity Size Index (HWISI) was 60.4. Typhoon Doksuri was similar in size and intensity to Hurricane Wilma just before Wilma hit the Yucatan Peninsula in 2005. Doksuri was capable of causing widespread severe damage.

Typhoon Doksuri will move through an environment very favorable for a powerful typhoon during the next 24 hours. Doksuri will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Doksuri could maintain its intensity during the next 24 hours unless an eyewall replacement cycle occurs. If the inner end of a rainband wraps around the existing eye and eyewall at the core of Doksuri, then concentric eyewalls could form. If concentric eyewalls, form, then an eyewall replacement cycle could cause Typhoon Doksuri to weaken.

Typhoon Doksuri will move around the southwestern side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Doksuri toward the northwest during the next 24 hours. On its anticipated track, the core of Typhoon Doksuri could pass just north of Escarpada Point in northeastern Luzon. The strongest part of Doksuri could affect the Babuyan Islands and the Batanes Islands north of Luzon. Doksuri will bring extremely strong winds and very heavy rain to the Babuyan Islands and the Batanes Islands. Heavy rain could cause flash floods in some locations. Typhoon Doksuri could cause a storm surge of up to 15 feet (5 meters) along the coast of some of the islands where the wind pushes water toward the shore. Heavy rain could also fall over parts of northern Luzon. The core of Doksuri could be south of Taiwan in 36 hours.

Typhoon Doksuri Rapidly Intensifies to Equivalent of a Major Hurricane

Typhoon Doksuri rapidly intensified to the equivalent of a major hurricane on Sunday. At 11:00 p.m. EDT on Sunday the center of Typhoon Doksuri was located at latitude 15.5°N and longitude 126.3°E which put it about 390 miles (615 km) southeast of Aparri, Philippines. Doksuri was moving toward the west-northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h). The minimum surface pressure was 956 mb.

Typhoon Doksuri rapidly intensified to the equivalent of a major hurricane over the Western North Pacific Ocean east of Luzon on Sunday. An eye with a diameter of 40 miles (65 km) was at the center of Doksuri’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Doksuri. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon. The removal of large quantities of mass caused the surface pressure to decrease rapidly.

The size of the circulation around Typhoon Doksuri increased when Doksuri rapidly intensified. Winds to typhoon force extended out 70 miles (110 km) from the center of Doksuri’s circulation. Winds to tropical storm force extended out 220 miles (355 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Doksuri was 20.6. The Hurricane Size Index (HSI) was 22.7 and the Hurricane Wind Intensity Size Index (HWISI) was 43.3. Doksuri was capable of causing widespread major damage.

Typhoon Doksuri will move through an environment very favorable for intensification during the next 24 hours. Doksuri will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Doksuri will continue to intensify during the next 24 hours. Doksuri could intensify rapidly at times.

Typhoon Doksuri will move around the southwestern side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Doksuri toward the northwest during the next 24 hours. On its anticipated track, Typhoon Doksuri could be near northeastern Luzon within 36 hours. Doksuri could approach southern Taiwan in 60 hours.

Doksuri Rapidly Intensifies to a Typhoon

Former Tropical Storm Doksuri rapidly intensified to a typhoon over the Western North Pacific Ocean east of Luzon on Sunday. At 11:00 a.m. EDT on Sunday the center of Typhoon Doksuri was located at latitude 15.2°N and longitude 127.4°E which put it about 475 miles (765 km) southeast of Aparri, Philippines. Doksuri was moving toward the west-northwest at 8 m.p.h. (13 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 972 mb.

Former Tropical Storm Doksuri rapidly intensified to a typhoon during the past 12 hours. The inner end of a rainband wrapped around the center of Doksuri’s circulation. An eye at the center of circulation was evident on conventional and microwave satellite images. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Doksuri. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon. The removal of large quantities of mass caused the surface pressure to decrease rapidly.

The size of the circulation around Typhoon Doksuri increased while Doksuri rapidly intensified. Winds to typhoon force extended out 70 miles (110 km) from the center of Doksuri’s circulation. Winds to tropical storm force extended out 215 miles (345 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Doksuri was 13.9. The Hurricane Size Index (HSI) was 22.1 and the Hurricane Wind Intensity Size Index (HWISI) was 36.0.

Typhoon Doksuri will move through an environment very favorable for intensification during the next 24 hours. Doksuri will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Doksuri is likely to continue to intensify rapidly during the next 24 hours. Doksuri could strengthen to the equivalent of a major hurricane.

Typhoon Doksuri will move around the southwestern side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Doksuri toward the northwest during the next 24 hours. On its anticipated track, Typhoon Doksuri could be near northeastern Luzon within 48 hours. Doksuri could approach southern Taiwan in 72 hours.

Tropical Storm Doksuri Intensifies East of the Philippines

Tropical Storm Doksuri intensified east of the Philippines on Saturday. At 11:00 p.m. EDT on Saturday the center of Tropical Storm Doksuri was located at latitude 14.9°N and longitude 128.7°E which put it about 830 miles (1340 km) southeast of Taipei, Taiwan. Doksuri was moving toward the west-northwest at 8 m.p.h. (13 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 989 mb.

Tropical Storm Doksuri exhibited better organization as it intensified over the Western North Pacific Ocean east of the Philippines on Saturday. The inner end of a rainband wrapped around the eastern side of the center of Doksuri’s circulation. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. More thunderstorms developed in bands in the eastern half of Tropical Storm Doksuri. Bands in the western half of Doksuri still consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 115 miles (185 km) from the center of Doksuri.

Tropical Storm Doksuri will move through an environment favorable for intensification during the next 24 hours. Doksuri will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Doksuri will intensify during the next 24 hours. Doksuri is likely to strengthen to a typhoon on Sunday.

Tropical Storm Doksuri will move around the southwestern side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Doksuri toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Doksuri will move closer to northern Luzon. Doksuri could reach Taiwan in less than four days.

Don Strengthens to a Hurricane over the Gulf Stream

Former Tropical Storm Don strengthened to a hurricane over the Gulf Stream on Saturday afternoon. At 5:00 p.m. EDT on Saturday the center of Hurricane Don was located at latitude 40.1°N and longitude 50.0°W which put it about 480 miles (775 km) south-southeast of Cape Race, Newfoundland. Don was moving toward the north 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 988 mb.

Former Tropical Storm Don intensified to a hurricane as it moved over the warm water in the Gulf Stream on Saturday afternoon. A small circular eye formed at the center of Hurricane Don. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Don. Storms near the core generated upper level divergence that pumped mass away from the hurricane. The removal of mass allowed the surface pressure to decrease to 988 mb at the center of Hurricane Don.

The circulation around Hurricane Don was small. Winds to hurricane force extended out 15 miles (25 km) from the center of Don’s circulation. Winds to tropical storm force extended out 70 miles (110 km) from the center of circulation.

Hurricane Don will move into an environment that will be very unfavorable for a hurricane during the next 24 hours. Don will move north of the Gulf Stream where the Sea Surface Temperatures are colder than 26˚C. An upper level trough over eastern Canada will produce southwesterly winds that will blow toward the top of Don’s circulation. Those winds will cause the vertical wind shear to increase on Sunday. The combination of much colder water and more vertical wind shear will cause Hurricane Don to weaken during the next 24 hours.

Hurricane Don will move around the northwestern part of a hurricane pressure system over the eastern Atlantic Ocean. The high pressure system and the upper level trough over eastern Canada will steer Don toward the northeast during the next 24 hours. On its anticipated track, Hurricane Don will stay southeast of Newfoundland.

Tropical Storm Don Spins South-southeast of Newfoundland

Tropical Storm Don was spinning over the Atlantic Ocean south-southeast of Newfoundland on Friday morning. At 11:00 a.m. EDT on Friday the center of Tropical Storm Don was located at latitude 35.8°N and longitude 46.5°W which put it about 825 miles (1330 km) south-southeast of Cape Race, Newfoundland. Don was moving toward the west-northwest at 10 m.p.h. (16 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 1002 mb.

The circulation around Tropical Storm Don was well organized on Friday morning. The inner end of a rainband wrapped around the center of Don’s circulation. A clear area was visible on satellite images at the center of Tropical Storm Don. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. The circulation around Tropical Storm Don was small. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Tropical Storm Don will move through an environment that will be marginally favorable for intensification during the next 24 hours. Don will move over water where the Sea Surface Temperatures are near 25˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Don could intensify during the next 24 hours. Don will move over the warmer water of the Gulf Stream for a brief time on Saturday. Tropical Storm Don could strengthen while it is over the Gulf Stream, but Don will then move over much colder water when it gets north of the Gulf Stream.

Tropical Storm Don will move around the western part of a high pressure system over the northeastern Atlantic Ocean. The high pressure system will steer Don toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Don will continue to make a big clockwise loop over the Central Atlantic south of Newfoundland.

Tropical Storm Doksuri Forms East of the Philippines

Tropical Storm Doksuri formed east of the Philippines on Thursday night. At 11:00 p.m. EDT on Thursday the center of Tropical Storm Doksuri was located at latitude 14.0°N and longitude 133.0°E which put it about 620 miles (1000 km) east of Legazpi, Philippines. Doksuri was moving toward the north-northwest at 9 m.p.h. (15 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 1002 mb.

A low pressure system over the Western North Pacific Ocean east of the Philippines strengthened on Thursday night and the Japan Meteorological Agency designated the system as Tropical Storm Doksuri. The circulation around Tropical Storm Doksuri exhibited more organization on satellite images. More thunderstorms developed in bands revolving around the center of Doksuri’s circulation. Storms near the center of circulation began to generate upper level divergence that pumped mass away from the tropical storm.

Tropical Storm Doksuri will move through an environment favorable for intensification during the next 48 hours. Doksuri will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the middle of an upper level ridge east of the Philippines. The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear. Tropical Storm Doksuri will intensify during the next 48 hours. Doksuri is likely to strengthen to a typhoon during the weekend.

Tropical Storm Doksuri will move around the southwestern side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Doksuri slowly toward the northwest during the next 48 hours. On its anticipated track, Tropical Storm Doksuri will move closer to northern Luzon.

Tropical Storm Don Strengthens over the Central Atlantic

Tropical Storm Don strengthened over the Central Atlantic Ocean on Wednesday night. At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Don was located at latitude 33.9°N and longitude 40.9°W which put it about 825 miles (1330 km) west-southwest of the Azores. Don was moving toward the west at 6 m.p.h. (10 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 1002 mb.

Tropical Storm Don strengthened on Wednesday night as it continued to make a big clockwise loop over the Central Atlantic Ocean west of the Azores. Don looked more like a tropical storm on satellite images. The shape of the cloud pattern was more circular. Thunderstorms formed along the inner end of a band just to the east of the center of Don’s circulation. Other bands of showers and thunderstorms were revolving around the center of Tropical Storm Don. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 70 miles (110 km) from the center of Don’s circulation.

Tropical Storm Don will move through an environment favorable for intensification during the next 24 hours. Don will move over water where the Sea Surface Temperatures are near 25˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Don will intensify during the next 24 hours.

Tropical Storm Don will move around the southwestern part of a high pressure system over the northeastern Atlantic Ocean during the next 24 hours. The high pressure system will steer Don slowly toward the west. On its anticipated track, Tropical Storm Don will continue to make a big clockwise loop over the Central Atlantic west of the Azores.

Tropical Storm Calvin Brings Gusty Winds and Rain to Hawaii

Tropical Storm Calvin brought gusty winds and rain to Hawaii on Wednesday. At 8:00 a.m. EDT on Wednesday the center of Tropical Storm Calvin was located at latitude 17.7°N and longitude 155.6°W which put it about 160 miles (260 km) south of Hilo, Hawaii. Calvin was moving toward the west at 20 m.p.h. (32 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 1003 mb.

A Tropical Storm Warning was in effect for Hawaii County.

After Tropical Storm Calvin strengthened late on Tuesday, it started to weaken again on Wednesday morning. An upper level trough northwest of Hawaii was producing southwesterly winds that were blowing toward the top of Calvin’s circulation. There were strong easterly winds in the lower levels of the atmosphere. The combination of southwesterly winds in the upper troposphere and easterly winds in the lower levels of the atmosphere caused strong vertical wind shear. The winds in the upper troposphere blew the top part of Tropical Storm Calvin toward the northeast. The strong easterly winds near the surface pushed the lower part of Calvin quickly toward the west.

The strong vertical wind shear caused Tropical Storm Calvin to weaken on Wednesday morning. The center of Calvin at the surface was passing south of the Big Island of Hawaii. Bands revolving around the center at the surface consisted primarily of showers and lower clouds. Thunderstorms were occurring in bands in the northern side of Tropical Storm Calvin where the wind was pushing air up the eastern slopes of the Hawaiian Islands. Winds to tropical storm force extended out 140 miles (220 km) in the northern side of Calvin’s circulation. Winds in the southern part of Calvin were blowing at less than tropical storm force.

Tropical Storm Calvin will move through an environment unfavorable for intensification during the next 24 hours. Calvin will move over water where the Sea Surface Temperatures are near 26˚C. However, the upper level trough northwest of Hawaii will continue to cause strong vertical wind shear. Tropical Storm Calvin will weaken to a tropical depression during the next 24 hours.

Tropical Storm Calvin will continue to produce gusty winds and locally heavy rain in Hawaii during the next 24 hours. The strongest wind gusts will occur at higher elevations. Calvin could cause isolated minor wind damage. Locally heavy rain could cause flooding in some locations. Flood Watches are in effect for the Big Island of Hawaii, Maui, Molokai, Lanai, and Kahoolawe.

Tropical Storm Calvin Speeds Toward Hawaii

Tropical Storm Calvin sped toward Hawaii on Tuesday. At 2:00 p.m. EDT on Tuesday the center of Tropical Storm Calvin was located at latitude 17.6°N and longitude 150.5°W which put it about 330 miles (640 km) east-southeast of Hilo, Hawaii. Calvin was moving toward the west at 22 m.p.h. (35 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 1002 mb.

A Tropical Storm Warning was in effect for Hawaii County.

Tropical Storm Calvin appeared to be getting stronger on Tuesday afternoon. More thunderstorms formed near the center of Calvin’s circulation. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. Even though Tropical Storm Calvin appeared to be strengthening, the vertical structure of Calvin’s circulation seemed to tilt a little to the north in the middle and upper levels of the troposphere. Winds to tropical storm force extended out 105 miles (165 km) in the northern side of Tropical Storm Calvin. Winds to tropical storm force extended out 25 miles (40 km) in the southern side of Calvin.

Tropical Storm Calvin will move through an environment that will be somewhat favorable for intensification during the next 24 hours. Calvin will move over water where the Sea Surface Temperatures will increase to 26˚C. It will move through a region where the upper level winds are blowing from the south. Those winds are not very strong, but they will cause some vertical wind shear. Tropical Storm Calvin could strengthen during the next 24 hours in spite of the vertical wind shear.

Tropical Storm Calvin will move around the southern part of a subtropical high pressure system over the Eastern and Central Pacific Ocean. The high pressure system will steer Calvin toward the west during the next several days. On its anticipated track, Tropical Storm Calvin will move near the Big Island of Hawaii on Tuesday night. Calvin will bring gusty winds and locally heavy rain to Hawaii on Tuesday night and Wednesday. Flood Watches are in effect for the Big Island of Hawaii, Maui, Molokai, Lanai, and Kahoolawe.