Tag Archives: HWISI

Typhoon Khanun Approaches Okinawa

Typhoon Khanun was approaching Okinawa on Monday night. At 11:00 p.m. EDT on Monday the center of Typhoon Khanun was located at latitude 24.8°N and longitude 129.1°E which put it about 165 miles (265 km) southeast of Okinawa. Khanun was moving toward the west-northwest at 12 m.p.h. (19 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. (265 km/h). The minimum surface pressure was 930 mb.

Typhoon Khanun continued to strengthen on Monday. A circular eye with a diameter of 30 miles (50 km) was at the center of Khanun’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 Khanun. Storms near the core generated strong upper level divergence that pumped mass away form the typhoon in all directions.

The core of Typhoon Khanun contracted on Monday as Khanun intensified. Winds to typhoon force extended out 50 miles (80 km) from the center of Khanun’s circulation. Winds to tropical storm force extended out 265 miles (425 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Khanun was 28.3. The Hurricane Size Index (HSI) was 17.4 and the Hurricane Wind Intensity Size Index (HWISI) was 45.7. Khanun is capable of causing regional severe damage. Typhoon Khanun was almost as strong as Hurricane Ida was when Ida hit Louisiana in 2021. Khanun was larger than Ida was.

Typhoon Khanun will move through an environment that will be favorable for a strong typhoon during the next 24 hours. Khanun will move over water where the Sea Surface Temperatures are near 29˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Khanun could intensify 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, then concentric eyewalls could develop. The formation of concentric eyewalls would cause Khanun to weaken.

Typhoon Khanun will move around the southwestern side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Khanun toward the west-northwest during the next 24 hours. On its anticipated track, the core of Typhoon Khanun will be just south of Okinawa in 12 hours. Khanun will bring strong, gusty winds and locally heavy rain to Okinawa and the other southern Ryukyu Islands. Heavy rain will cause flash floods in some locations. Typhoon Khanun will also cause a significant storms surge in the parts of islands where the winds blow water toward the coast.

Typhoon Khanun Rapidly Intensifies to Equivalent of a Major Hurricane

Typhoon Khanun rapidly intensified to the equivalent of a major hurricane southeast of Okinawa on Sunday. At 11:00 p.m. EDT on Sunday the center of Typhoon Khanun was located at latitude 22.3°N and longitude 133.7°E which put it about 405 miles (655 km) southeast of Okinawa. Khanun was moving toward the north-northwest 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 150 m.p.h. (240 km/h). The minimum surface pressure was 948 mb.

Typhoon Khanun rapidly intensified to the equivalent of a major hurricane on Sunday. A circular eye with a diameter of 30 miles (50 km) was at the center of Khanun’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 Khanun. Storms near the core generated strong upper level divergence that pumped mass away form the typhoon in all directions. The removal of large amounts of mass caused the surface pressure to decrease rapidly.

The circulation around Typhoon Khanun was large. Winds to typhoon force extended out 70 miles (110 km) from the center of Khanun’s circulation. Winds to tropical storm force extended out 290 miles (465 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Khanun was 22.1. The Hurricane Size Index (HSI) was 26.1 and the Hurricane Wind Intensity Size Index (HWISI) was 48.2. Typhoon Khanun was similar in size and intensity to Hurricane Jeanne when Jeanne hit Florida in 2004.

Typhoon Khanun will move through an environment that will be favorable for intensification during the next 24 hours. Khanun will move over water where the Sea Surface Temperatures are near 29˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Khanun is very likely to intensify during the next 24 hours. Khanun could intensify rapidly at times.

Typhoon Khanun will move around the southwestern side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Khanun toward the northwest during the next 24 hours. On its anticipated track, Typhoon Khanun will move toward the Ryukyu Islands. The center of Khanun could be just south of Okinawa in 36 hours.

Typhoon Doksuri Hits Eastern China

Typhoon Doksuri hit eastern China on Thursday night. At 11:00 p.m. EDT on Thursday the center of Typhoon Doksuri was located at latitude 24.8°N and longitude 118.5°E which put it about 35 miles (55 km) northeast of Xiamen, China. Doksuri was moving toward the north-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h). The minimum surface pressure was 940 mb.

The center of Typhoon Doksuri made landfall on the east coast of China between Xiamen and Quanzhou on Thursday night. Doksuri was bringing strong winds and heavy rain to Fujian. Winds to typhoon force extended out 40 miles (65 km) from the center of Doksuri’s circulation. Winds to tropical storm force extended out 140 miles (225 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Doksuri was 19.2. The Hurricane Size Index (HSI) was 13.6 and the Hurricane Wind Intensity Size Index (HWISI) was 32.8. Typhoon Doksuri was similar in size and intensity to Hurricane Sally when Sally hit Alabama in 2020.

Typhoon Doksuri will continue to move toward the north-northwest during the next 36 hours. On its anticipated track, Typhoon Doksuri will move inland over eastern China. Doksuri will weaken as it moves inland. The core of Typhoon Doksuri will bring strong winds to Fujian. Doksuri will also drop heavy rain over parts of Fujian. Heavy rain could cause flash floods in some locations. Doksuri will bring gusty winds and locally heavy rain to parts of Zhejiang and Jiangxi.

Elsewhere over the Western North Pacific Ocean, former Tropical Depression 06W strengthened to Tropical Storm Khanun east of the Philippines. At 11:00 p.m. EDT on Thursday the center of Tropical Storm Khanun was located at latitude 13.4°N and longitude 135.7°E which put it about 1060 miles (1710 km) south-southeast of Okinawa. Khanun was moving toward the west at 10 m.p.h. (16 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 1001 mb. Tropical Storm Khanun is forecast to move toward the Ryukyu Islands and to strengthen to a typhoon.

Typhoon Doksuri Moves over Taiwan Strait

Typhoon Doksuri moved over the Taiwan Strait on Thursday morning. At 11:00 a.m. EDT on Thursday the center of Typhoon Doksuri was located at latitude 22.3°N and longitude 119.0°E which put it about 170 miles (275 km) south-southeast of Xiamen China. Doksuri was moving toward the north-northwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 943 mb.

Radar images from Taiwan’s Central Weather Bureau showed clearly that there were concentric eyewalls at the core of Typhoon Doksuri. A small circular eye with a diameter of 7 miles (11 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. The inner eyewall was surrounded by a relatively clear area, sometimes called a moat. A much larger, outer eyewall with a diameter of 60 miles (95 km) surrounded the inner eyewall and the moat. Bands of showers and thunderstorms were revolving around the concentric eyewalls. Storms in the concentric eyewalls generated upper level divergence that pumped mass away from the typhoon.

Both the inner and outer eyewalls of Typhoon Doksuri were over the Taiwan Strait. Mountains in Taiwan were deflecting some of the wind circulating around the eastern side of Doksuri, and the core of circulation tightened up a little. Winds to typhoon force extended out 45 miles (75 km) from the center of Doksuri’s circulation. Winds to tropical storm force extended out 160 miles (260 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Doksuri was 22.1. The Hurricane Size Index (HSI) was 17.1 and the Hurricane Wind Intensity Size Index (HWISI) was 39.2. Typhoon Doksuri was bigger and stronger than Hurricane Delta when Delta hit Louisiana in 2020. Doksuri was capable of causing regional severe damage.

Typhoon Doksuri will move through an environment very favorable for intensification during the next 12 hours. Doksuri will move over water where the Sea Surface Temperatures are near 31˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. However, the concentric eyewalls at the center of Typhoon Doksuri will inhibit intensification. Doksuri could weaken if the inner eye and eyewall dissipate. If the inner eye and eyewall remain intact, then Typhoon Doksuri could strengthen during the next 12 hours.

Typhoon Doksuri will move around the western side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Doksuri toward the north-northwest during the next 24 hours. On its anticipated track, Typhoon Doksuri will approach the east coast of China near Xiamen in 24 hours. Doksuri will bring strong winds and heavy rain to Fujian. Heavy rain could cause flash floods in some locations. Typhoon Doksuri could also cause a storm surge of up to 13 feet (4 meters) along the coast of Fujian.

Bands in the eastern side of Typhoon Doksuri will continue to drop heavy rain on parts of Taiwan during the next 24 hours. The heaviest rain will fall initially on the eastern side of mountains where the winds around Doksuri will push air up the slopes. Heavy rain could fall on the western sides of mountains when Typhoon Doksuri moves farther north and the wind over Taiwan blows from the south. Heavy rain is likely to cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, a new tropical depression formed east of the Philippines. At 11:00 a.m. EDT on Thursday the center of Tropical Depression 06W was located at latitude 12.7°N and longitude 137.5°E which put it about 170 miles (275 km) northwest of Yap. The tropical depression was moving toward the west-northwest at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1003 mb. Tropical Depression 06W is forecast to move toward the Ryukyu Islands and to strengthen to a typhoon.

Typhoon Doksuri Brings Wind and Rain to the Northern Philippines

Typhoon Doksuri brought strong winds and heavy rain to the northern Philippines on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Typhoon Doksuri was located at latitude 19.2°N and longitude 121.3°E which put it about 40 miles (65 km) north-northeast of Claveria, Philippines. Doksuri was moving toward the west at 12 m.p.h. (19 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. (265 km/h). The minimum surface pressure was 936 mb.

Powerful Typhoon Doksuri brought strong winds and locally heavy rain to parts of northern Luzon, the Babuyan Islands, and the Batanes Islands on Tuesday. The eye of Typhoon Doksuri was just north of the coast of northern Luzon. The southern part of the eyewall of Doksuri was over the coast. Strong winds in other parts of the eyewall of Typhoon Doksuri were pounding the Babuyan Islands and the Batanes Islands.

The circulation around Typhoon Doksuri continued to be very well organized even though the southern part of the typhoon was over northern Luzon. A circular eye with a diameter of 28 miles (44 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.

Doksuri continued to be a large typhoon. Winds to typhoon force extended out 70 miles (110 km) from the center of Doksuri’s circulation. Winds to tropical storm force extended out 230 miles (370 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Doksuri was 28.3. The Hurricane Size Index (HSI) was 26.9 and the Hurricane Wind Intensity Size Index (HWISI) was 55.2. Typhoon Doksuri was similar in size and intensity to Hurricane Frances when Frances was east of Florida in 2004. Doksuri was capable of causing widespread severe damage.

Typhoon Doksuri will move through an environment 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. However, much of the circulation around the southern part of Typhoon Doksuri will pass over northern Luzon. The flow of air over land is likely to somewhat disrupt the circulation around Doksuri. In addition, some of the circulation around the northern side of Doksuri will pass over Taiwan on Wednesday. Interactions with land are likely to cause Typhoon Doksuri to weaken during the next 24 hours.

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 will move slowly away from northern Luzon during the next 24 hours. The strongest part of Doksuri will continue to lash the Babuyan Islands and the Batanes Islands north of Luzon until the typhoon moves farther away. Doksuri will produce strong winds and very heavy rain in the Babuyan Islands and the Batanes Islands for another 24 hours. 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 will also continue to fall over parts of northern Luzon on Wednesday. The core of Doksuri could be south of Taiwan in less than 24 hours. Typhoon Doksuri will bring strong winds and locally heavy rain to parts of Taiwan. The heaviest rain will fall on the eastern side of mountains where the winds around Doksuri will push air up the slopes.

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.

Hurricane Calvin Churns Toward the Central Pacific

Hurricane Calvin churned toward the Central Pacific Ocean on Saturday. At 5:00 p.m. EDT on Saturday the center of Hurricane Calvin was located at latitude 15.0°N and longitude 130.4°W which put it about 1660 miles (2670 km) east of Hilo, Hawaii. Calvin was moving toward the west at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h). The minimum surface pressure was 975 mb.

Hurricane Calvin weakened on Saturday when it moved over cooler water east of Hawaii. Thunderstorms around the center of Calvin’s circulation did not rise as high into the atmosphere. The structure of Hurricane Calvin remained well organized even though the hurricane was weaker. A small circular eye was still present at the center of Calvin’s circulation. The eye was surrounded by a broken 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 Calvin. Storms near the core still generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Calvin was small. Winds to hurricane force extended out 25 miles (40 km) from the center of Calvin’s circulation. Winds to tropical storm force extended out 105 miles (165 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Calvin was 16.5. The Hurricane Size Index (HSI) was 9.3 and the Hurricane Wind Intensity Size Index (HWISI) was 25.8.

Hurricane Calvin will move through an environment that will be unfavorable for intensification during the next 24 hours. Calvin will move over water where the Sea Surface Temperatures are near 25˚C. It will move through a region where then upper level winds that are weak and there will be little vertical wind shear. Hurricane Calvin will continue to weaken during the next 24 hours because of the cooler water even though there will be little vertical wind shear.

Hurricane 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, Hurricane Calvin will continue to move toward the Central Pacific Ocean. Calvin could approach Hawaii on Tuesday. Calvin could still be a tropical storm when it approaches Hawaii.

Calvin Rapidly Intensifies to a Major Hurricane

Hurricane Calvin rapidly intensified to a major hurricane over the Eastern North Pacific Ocean on Friday morning. At 11:00 a.m. EDT on Friday the center of Hurricane Calvin was located at latitude 13.6°N and longitude 123.2°W which put it about 1080 miles (1740 km) southwest of the southern tip of Baja California. Calvin was moving toward the west at 16 m.p.h. (26 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 960 mb.

Hurricane Calvin rapidly intensified to a major hurricane over the Eastern North Pacific Ocean southwest of Baja California on Friday morning. A small circular eye with a diameter of 17 miles (28 km) formed at the center of Calvin’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 Hurricane Calvin. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The size of the circulation around Hurricane Calvin increased as Calvin rapidly intensified. Winds to hurricane force extended out 30 miles (50 km) from the center of Calvin’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center. The Hurricane Intensity Index (HII) for Hurricane Calvin was 22.1. The Hurricane Size Index (HSI) was 10.3 and the Hurricane Wind Intensity Size Index (HWISI) was 32.4.

Hurricane Calvin will move through an environment that will be favorable for intensification during the next 12 hours. Calvin will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where then upper level winds that are weak and there will be little vertical wind shear. Hurricane Calvin could intensify during the next 12 hours. Calvin will move over cooler water on Saturday. Hurricane Calvin is likely to weaken when it moves over the cooler water.

Hurricane Calvin will move around the southern part of a subtropical high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Calvin toward the west during the next several days. On its anticipated track, Hurricane Calvin will move toward the Central Pacific Ocean. Calvin could approach Hawaii on Tuesday. Calvin could still be a tropical storm when it approaches Hawaii.