Tag Archives: Hilo

Fernanda Rapidly Intensifies to a Major Hurricane

Hurricane Fernanda rapidly intensified to a major hurricane over the Eastern North Pacific Ocean during Sunday night. At 5:00 a.m. EDT on Monday the center of Hurricane Fernanda was located at latitude 15.6°N and longitude 117.7°W which put it about 715 miles (1150 km) southwest of the southern tip of Baja California. Fernanda was moving toward the west at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 959 mb.

Hurricane Fernanda continued to intensify rapidly during Sunday night. A small eye was at the center of Fernanda’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 revolved around the core of Hurricane Fernanda. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Fernanda was small. Winds to hurricane force extended out 25 miles (40 km) from the center of Fernanda’s circulation. Winds to tropical storm force extended out 70 miles (110 km) from the center of circulation. The Hurricane Intensity Index (HII) was 23.6. The Hurricane Size Index (HSI) was 7.8 and the Hurricane Wind Intensity Size Index (HWISI) was 31.4.

Hurricane Fernanda will move through an environment favorable for intensification during the next 12 hours. Fernanda 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. Hurricane Fernanda is likely to continue to intensify during the next 12 hours. Fernanda will move over slightly cooler water on Tuesday. The cooler water will cause Fernanda to start to weaken.

Hurricane Fernanda will move south of a subtropical high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Fernanda toward the west during the next 24 hours. On its anticipated track, Hurricane Fernanda will move farther away from Baja California.

Elsewhere, Tropical Storm Greg formed east-southeast of Hawaii. At 5:00 a.m. EDT on Monday the center of Tropical Storm Greg was located at latitude 11.3°N and longitude 139.8°W which put it about 1170 miles (1885 km) east-southeast of Hilo, Hawaii. Greg was moving toward the west at 13 m.p.h. (21 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 1005 mb. Tropical Storm Greg is forecast to pass south of Hawaii later this week.

Hurricane Dora Moves Southeast of Hawaii

Hurricane Dora moved southeast of Hawaii on Monday. At 11:00 p.m. EDT on Monday the center of Hurricane Dora was located at latitude 12.0°N and longitude 152.3°W which put it about 565 miles (905 km) south-southeast of Hilo, Hawaii. Dora was moving toward the west at 23 m.p.h. (37 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 155 m.p.h. (250 km/h). The minimum surface pressure was 953 mb.

Hurricane Dora weakened slightly on Monday. The structure of Dora continued to be very symmetrical. An eye with a diameter of 12 miles (19 km) was at the center of Hurricane Dora. 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 Dora’s circulation. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The size of the circulation around Hurricane Dora increased a little on Monday. Winds to hurricane force extended out 30 miles (50 km) from the center of Dora’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) was 25.1. The Hurricane Size Index (HSI) was 9.9 and the Hurricane Wind Intensity Size Index (HWISI) was 35.0.

Hurricane Dora will move through an environment that will be favorable for a major hurricane during the next 24 hours. Dora will move over water where the Sea Surface Temperatures are near 26.5°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Dora could move into a region where the air is a little drier. Since the circulation around Hurricane Dora is so small, any changes in the environment will have large effects on the intensity of Dora. Hurricane Dora could weaken a little more during the next 24 hours because of the drier air.

Hurricane Dora will move south of a subtropical high pressure system over the North Pacific Ocean. The high pressure system will steer Dora toward the west during the next 24 hours. On its anticipated track, Hurricane Dora will pass south of Hawaii on Tuesday.

Elsewhere, former Tropical Storm Eugene weakened west of Baja California on Monday. At 5:00 p.m. EDT on Monday the center of Tropical Depression Eugene was located at latitude 25.1°N and longitude 120.4°W which put it about 680 miles (1095 km) west-northwest of the southern tip of Baja California. Eugene was moving toward the west-northwest at 14 m.p.h. (22 km/h). 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 1008 mb.

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.

Calvin Prompts Tropical Storm Watch for Hawaii

The potential impacts of Tropical Storm Calvin prompted the issuance of a Tropical Storm Watch for Hawaii. At 11:00 a.m. EDT on Monday the center of Tropical Storm Calvin was located at latitude 16.8°N and longitude 141.4°W which put it about 920 miles (1480 km) east of Hilo, Hawaii. Calvin was moving toward the west at 18 m.p.h. (30 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 1000 mb.

A Tropical Storm Watch was in effect for Hawaii County.

The U.S. Central Pacific Hurricane Center issued a Tropical Storm Watch for Hawaii County on Monday morning because of the potential effects of Tropical Storm Calvin. Former Hurricane Calvin weakened to a tropical storm on Sunday as it moved over cooler water east of Hawaii. Tropical Storm Calvin moved over water where the Sea Surface Temperatures were near 24˚C. Less energy was transported into the atmosphere from the cooler water and many of the thunderstorms in Calvin’s circulation dissipated. The bands revolving around the center of Tropical Storm Calvin consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 105 miles (165 km) in the northern side of Calvin’s circulation. Winds to tropical storm force extended out 60 miles (95 km) in the southern side of the circulation.

Tropical Storm Calvin will move through an environment that will be mostly 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. Tropical Storm Calvin could continue to weaken during the next 24 hours because of the cooler water even though there will be little vertical wind shear. Calvin will move over slightly warmer water when it gets closer to Hawaii.

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 Hawaii on Tuesday night. Calvin could still be a tropical storm when it approaches Hawaii. Tropical Storm Calvin will bring gusty winds and locally heavy rain to Hawaii on Tuesday night and Wednesday.

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.

Tropical Storm Estelle Forms South of Mexico

Tropical Storm Estelle formed over the Eastern North Pacific Ocean south of Mexico on Friday night. At 11:00 p.m. EDT on Friday the center of Tropical Storm Estelle was located at latitude 13.2°N and longitude 102.0°W which put it about 290 miles (470 km) south-southwest of Acapulco, Mexico. Estelle was moving toward the northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1006 mb.

An area of low pressure over the Eastern North Pacific Ocean south of Mexico strengthened on Friday night and the National Hurricane Center designated the system as Tropical Storm Estelle. The circulation around Estelle exhibited more organization. More thunderstorms developed near the center of Tropical Storm Estelle. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. Bands of showers and thunderstorms were revolving around the center of Estelle’s circulation. Winds to tropical storm force extended out 45 miles (75 km) in the northeastern quadrant of Tropical Storm Estelle. The wind in the other parts of Estelle’s circulation were blowing at less than tropical storm force.

Tropical Storm Estelle will move through an environment favorable for intensification during the next 36 hours. Estelle will move over water where the Sea Surface Temperatures are near 28˚C. It will move under an upper level ridge near the west coast of Mexico. The upper level winds are weak in the ridge and there will be little vertical wind shear. Tropical Storm Estelle will intensify during the next 36 hours and it could strengthen to a hurricane.

Tropical Storm Estelle will move around the southern side of a high pressure system over Mexico. The high pressure system will steer Estelle toward the west-northwest during the next 36 hours. On its anticipated track Tropical Storm Estelle will move away from the west coast of Mexico.

Elsewhere, Tropical Storm Darby weakened east-southeast of Hawaii. At 11:00 p.m. EDT on Friday the center of Tropical Storm Darby was located at latitude 17.7°N and longitude 149.4°W which put it about 400 miles (640 km) east-southeast of Hilo, Hawaii. Darby was moving toward the west at 20 m.p.h. (32 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1006 mb.

Hurricane Darby Moves over the Central Pacific

Hurricane Darby moved over the Central Pacific Ocean on Thursday morning. At 11:00 a.m. EDT on Thursday the center of Hurricane Darby was located at latitude 16.6°N and longitude 140.9°W which put it about 955 miles (1540 km) east of Hilo, Hawaii. Darby was moving toward the west-northwest at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 977 mb.

Hurricane Darby moved west of longitude 140°W west on Thursday morning which meant that it crossed from the Eastern North Pacific basin to the Central Pacific. A small eye persisted at the center of Darby’s circulation. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Storms near the center of circulation generated upper level divergence that pumped mass away from the hurricane. The circulation around Hurricane Darby was small. Winds to hurricane force extended out 20 miles (30 km) from the center of Darby. Winds to tropical storm force extended out 45 miles (75 km) from the center of circulation.

Hurricane Darby will move into an environment unfavorable for intensification during the next 36 hours. Darby will move over water where the Sea Surface Temperatures are near 26˚C. An upper level trough located to the northwest of Hurricane Darby will produce southwesterly winds that will blow toward the top of Darby’s circulation. Those winds will cause the vertical wind shear to increase. More wind shear will cause Hurricane Darby to weaken. Since the circulation around Hurricane Darby is so small, the vertical wind shear could cause Darby to weaken quickly.

Hurricane Darby will move around the southern side of a high pressure system over the Central Pacific Ocean. The high pressure system will steer Darby toward the west during the next 36 hours. On its anticipated track Hurricane Darby could be southeast of Hawaii by Saturday. Darby is forecast to be much weaker by that time.

Possible Development East-Northeast of Hawaii

The National Hurricane Center (NHC) indicated that a low pressure system over the Eastern North Pacific Ocean east-northeast of Hawaii could develop into a subtropical or a tropical cyclone during the next 48 hours. The low pressure system is currently designated as Invest 90E. At 1:00 p.m. EST on Thursday the center of Invest 90E was located at latitude 21.8°N and longitude 136.1°W which put it about 1280 miles (2065 km) east-northeast of Hilo, Hawaii. It was moving toward the west-northwest at 12 m.p.h. (19 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 1006 mb.

The National Hurricane Center issued a Special Tropical Weather Outlook on Thursday afternoon which indicated that a low pressure system over the Eastern North Pacific Ocean had a 40% probability of development into a subtropical or a tropical cyclone during the next 48 hours. The low pressure system has been moving slowly toward the west between Baja California and Hawaii. The low pressure system currently has a hybrid structure. A well organized low level center of circulation was evident on visible satellite images. The low level center was located just to the east of a low pressure system in the middle and upper troposphere. The upper low was producing southerly winds that were blowing toward the top of the low level circulation. Those winds were causing moderate vertical wind shear and the wind shear was affecting the structure of the system. The strongest thunderstorms were occurring in bands north and east of the low level center of circulation. Bands south and west of the low level center consisted primarily of showers and lower clouds.

Invest 90E will move through an environment somewhat favorable for the formation of a subtropical or a tropical cyclone during the next 24 hours. The surface center of circulation will move over water where the Sea Surface Temperatures are near 24˚C. Since the upper low contains colder air, that water temperature is warm enough to support the development of a subtropical or a tropical cyclone. The low in the middle and upper troposphere will continue to cause moderate vertical wind shear. The wind shear will inhibit the development of a tropical cyclone. The current hybrid structure of Invest 90E and the marginally warm Sea Surface Temperatures would favor the development of a subtropical cyclone. However, if the strength of the upper level winds decreases, then a tropical cyclone could form.

Invest 90E will move south of a surface high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer the low level center of circulation toward the west-northwest during the next 24 hours. On its anticipated track Invest 90E will move slowly toward the Central Pacific Ocean.

Tropical Storm Jimena Develops East-southeast of Hawaii

Tropical Storm Jimena developed east-southeast of Hawaii on Thursday morning. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Jimena was located at latitude 15.5°N and longitude 136.6°W which put it about 1265 miles (2040 km) east-southeast of Hilo, Hawaii. Jimena was moving toward the northwest at 7 m.p.h. (11 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 1005 mb.

More thunderstorms developed near the center of former Tropical Depression Nine-E on Thursday morning and the National Hurricane Center upgraded the system to Tropical Storm Jimena. The circulation around Jimena was asymmetrical. Many of the stronger thunderstorms were developing in the eastern half of Tropical Storm Jimena. Bands in the western half of Jimena consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 40 miles (65 km) in the northeastern quadrant of the circulation. The winds in the other parts of Jimena were blowing at less that tropical storm force.

Tropical Storm Jimena will move through an environment only marginally favorable for intensification during the next 24 hours. Jimena will move over water where the Sea Surface Temperatures are near 26°C. It will move through an area where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Jimena will move over cooler water on Friday. Jimena could strengthen a little during the next 24 hours, but it is likely to weaken when it moves over cooler water.

Tropical Storm Jimena will move around the southern side of a subtropical high pressure system over the Eastern North Pacific Ocean. The high will steer Jimena toward the west-northwest during the next several days. On its anticipated track Tropical Storm Jimena could be east-northeast of Hawaii in a few days.

Elsewhere over the Eastern North Pacific Ocean, Tropical Storm Hilda was weakening to the northeast of Tropical Storm Jimena. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Hilda was located at latitude 20.1°N and longitude 129.2°W which put it about 1255 miles (2020 km) west of the southern tip of Baja California. Hilda was moving toward the west-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 1005 mb.