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Recon Finds Hurricane Hector Nearly at Category 5

An Air Force Reserve Hurricane Hunter reconnaissance aircraft found on Monday that Hurricane Hector had strengthened to nearly Category 5 on the Saffir-Simpson Scale.  At 5:00 p.m. EDT on Monday the center of Hurricane Hector was located at latitude 15.2°N and longitude 143.1°W which put it about 870 miles (1405 km) east-southeast of South Point, Hawaii.  Hector was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h).  The minimum surface pressure was 936 mb.  A Tropical Storm Watch is in effect for Hawaii County.

Hurricane Hector has a very symmetrical, well formed circulation.  There is a circular eye with a diameter of 19 miles (31 km) at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Hector.  Storms near the core were generating well developed upper level divergence which was pumping mass away from the hurricane in all directions.

The circulation of Hurricane Hector is compact.  Winds to hurricane force extend out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extend out about 105 miles (170 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Hector is 33.3.  The Hurricane Size Index (HSI) is 12.1 and the Hurricane Wind Intensity Size Index (HWISI) is 45.4.

Hurricane Hector will remain in its current environment for several more days.  Hector will move over water where the Sea Surface Temperature is near 27°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  If a rainband wraps around the eye and eyewall, then an eyewall replacement cycle could occur.  Eyewall replacement cycles cause weakening at first while the inner eyewall dissipates.  Hurricanes can restrengthen if the outer eyewall starts for move closer to the center of circulation.  Most very powerful hurricanes only stay very intense for 12 to 24 hours before they start to weaken.  If takes a lot of energy to drive an intense hurricane and if Hector moves into an environment that is a little less favorable, then it could weaken.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern and Central North Pacific Ocean.  The subtropical high will steer Hector in a general westerly direction during the next few days.  On its anticipated track Hurricane Hector will be southeast of Hawaii by Wednesday morning.  The core of Hurricane Hector is forecast to pass south of Hawaii, but it could come close enough to cause tropical storm force winds which is the reason for the Tropical Storm Watch.

Powerful Hurricane Hector Approaches Central Pacific, Ileana Forms South of Mexico

Powerful Hurricane Hector approached the Central Pacific Ocean on Sunday while Tropical Storm Ileana and Tropical Depression Twelve-E formed south of Mexico.  The government of Mexico issued a Tropical Storm Watch for a portion of the coast because of the potential impacts of Tropical Storm Ileana.  At 8:00 p.m. EDT on Sunday the center of Hurricane Hector was located at latitude 14.5°N and longitude 138.6°W which put it about 1170 miles (1885 km) east-southeast of South Point, Hawaii.  Hector was moving toward the west at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 165 m.p.h. (270 km/h).  The minimum surface pressure was 947 mb.

The circulation of Hurricane Hector was very well organized.  There was a circular eye with a diameter of 18 miles (29 km) at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Hector.  Storms in the core of Hector were generating strong upper level divergence which was pumping mass away from the hurricane.

The circulation of Hurricane Hector remained compact.  Winds to hurricane force extended out about 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Hector was 28.3.  The Hurricane Size Index (HSI) was 9,9 and The Hurricane Wind Intensity Size Index (HWISI) was 38.2.

Hurricane Hector will move through an environment capable of supporting a strong hurricane during the next day or two.  It will move over water where the Sea Surface Temperature is near 27°C and 28°C.  Hector will move through an area where the upper level winds are weak and there will be little vertical wind shear.  An eyewall replacement cycle could occur if a rainband wraps around the existing eye and eyewall.  It would cause fluctuations in the intensity of Hurricane Hector.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean.  The high will steer Hurricane Hector toward the west during the next several days.  On its anticipated track Hurricane Hector will be southeast of Hawaii in about three days.

Tropical Storm Ileana developed south of Mexico on Sunday.  The government of Mexico issued a Tropical Storm Watch for the portion of the coast from Lazaro Cardenas to Cabo Corrientes.  At 8:00 p.m. EDT on Sunday the center of Tropical Storm Ileana was located at latitude 13.9°N and longitude 98.9°W which put it about 210 miles (335 km) south-southeast of Acapulco, Mexico.  Ileana was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 1000 mb.

Tropical Depression Twelve-E formed west of Tropical Storm Ileana on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Depression Twelve-E was located at latitude 14.6°N and longitude 105.8°W which put it about 320 miles (515 km) south-southwest of Manzanillo, Mexico.  It was moving toward the northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1006 mb.

There is uncertainty about the future interaction of Tropical Storm Ileana and Tropical Depression Twelve-E.  The circulation of Tropical Depression Twelve-E is much larger than the circulation of Tropical Storm Ileana.  In addition, upper level divergence form the depression could cause vertical wind shear over Tropical Storm Ileana.  In one possible scenario Tropical Storm Ileana moves toward Tropical Depression Twelve-E and it is absorbed by the larger circulation.  Another possibility is that Tropical Storm Ileana moves around the eastern periphery of the circulation of the tropical depression,  The second scenario would bring Tropical Storm Ileana close to the west coast of Mexico which is why the Tropical Storm Watch was issued.

Hector Strengthens Into a Major Hurricane

Hurricane Hector strengthened to Category 3 on the Saffir-Simpson Scale on Friday night which made it a major hurricane.  At 11:00 p.m. EDT on Friday the center of Hurricane Hector was located at latitude 14.2°N and longitude 130.9°W which put it about 1640 miles (2640 km) east of Hilo, Hawaii.  Hector was moving toward the west at 12 m.p.h. (19 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. (225 km/h).  The minimum surface pressure was 967 mb.

Hurricane Hector strengthened on Friday night despite having a double eyewall structure.  There was a small inner eye surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  A clear ring sometimes called a moat surrounded the inner eyewall.  The moat was surrounded by an outer eyewall that consisted of showers and thunderstorms.  Several other bands of showers and thunderstorms were revolving around the concentric eyewalls.  Thunderstorms in the core of Hurricane Hector were generating strong upper level divergence which was pumping mass away from the hurricane in all directions.

The circulation of Hurricane Hector was small.  Winds to hurricane force only extended out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force only extended out about 70 miles (110 km) from the center.

Hurricane Hector will move through an environment favorable for intensification during the weekend.  Hector will move over water where the Sea Surface Temperature is between 27°C and 28°C.  It will move through an area where the upper level winds are weak.  However, the existence of concentric eyewalls means that an eyewall replacement cycle will occur at some time in the future.  The eyewall replacement will cause Hurricane Hector to weaken when the inner eyewall dissipates and the strongest winds are found in the outer eyewall.  Hector could begin to intensify again if the outer eyewall begins to contract closer to the center of circulation.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean and the high will steer Hector westward during the next few days.  On its anticipated track Hurricane Hector could be southeast of Hawaii in four or five days.

Hector Rapidly Intensifies Into a Hurricane

Former Tropical Storm Hector rapidly intensified a hurricane on Thursday morning.  At 11:00 a.m. EDT on Thursday the center of Hurricane Hector was located at latitude 14.2°N and longitude 124.6°W which put it about 1135 miles (1825 km) west-southwest of the southern tip of Baja California.  Hector was moving toward the west at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 987 mb.

The circulation of Hurricane Hector rapidly became more organized on Thursday morning.  A band of showers and thunderstorms wrapped tightly around the center of circulation.  A small eye appeared on satellite images at the center of Hurricane Hector.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several other bands of showers and thunderstorms were revolving around the core of the hurricane.  Storms near the core were generating strong upper level divergence which was pumping mass away from the hurricane.  The circulation of Hurricane Hector was relatively small.  Winds to hurricane force extended out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extended out about 60 miles (95 km) from the center.

Hurricane Hector will move through an environment favorable for intensification during the next several days.  Hector will move over water where the Sea Surface Temperature is between 27°C and 28°C.  An upper level ridge northeast of Hurricane Hector will produce easterly winds which will blow toward the top of the circulation.  However, the strongest easterly winds will be north of Hector and the vertical wind shear should not be too great over the hurricane.  Hurricane Hector is likely to continue to intensify and it could become a major hurricane.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean.  The subtropical high will steer Hector in a generally westerly direction during the next few days.  On its anticipated track Hurricane Hector will cross into the Central Pacific late in the weekend.  Hector could be southeast of Hawaii early next week.

Tropical Storm Hector Forms Southwest of Baja California

Tropical Storm Hector formed southwest of Baja California on Tuesday evening.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Hector was located at latitude 13.0°N and longitude 118.2°W which put it about 875 miles (1405 km) southwest of the southern tip of Baja California.  Hector was moving toward the west-northwest at 14 m.p.h. (22 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 1006 mb.

A distinct low level center of circulation formed within an area of thunderstorms southwest of Baja California on Tuesday and the National Hurricane Center designated the system as Tropical Storm Hector.  The circulation of Tropical Storm Hector was still organizing.  Many of the stronger thunderstorms were occurring in two bands south and west of the center of circulation.  Additional bands of showers and storms were developing north and southeast of the center.  Thunderstorms near the center were beginning to generate upper level divergence which was pumping mass away from the tropical storm.

Tropical Storm Hector will move through an environment that is mostly favorable for intensification.  Hector will move over water where the Sea Surface Temperature is near 28°C.  An upper level ridge centered near Baja California was generating northeasterly winds which were blowing toward the top of the circulation.  Those winds were causing some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Hector will intensify over the next several days and it will likely become a hurricane by Thursday night.

Tropical Storm Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean.  The subtropical high will steer Hector in a general westerly direction.  On its anticipated track Tropical Storm Hector will move away from Mexico and toward the Central Pacific Ocean.

Minimal Tropical Storm Gilma Forms Well East of Hawaii

Minimal Tropical Storm Gilma formed well east of Hawaii on Friday.  A scatterometer on a polar orbiting satellite indicated that there were winds to tropical storm force near former Tropical Depression Eight-E and the National Hurricane Center named the system Tropical Storm Gilma.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Gilma was located at latitude 14.9°N and longitude 128.4°W which put it about 1825 miles (2935 km) east of South Point, Hawaii.  Gilma was moving toward the west-northwest at 17 m.p.h. (28 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 1006 mb.

The circulation of Tropical Storm Gilma was poorly organized.  There was a distinct low level center of circulation.  However, the stronger thunderstorms were occurring in bands east of the center.  Bands in the western half of the circulation consisted primarily of low clouds and showers.  A large upper level trough was located west of Tropical Storm Gilma.  The trough was producing strong northwesterly winds which were blowing across the top of the circulation.  Those winds were producing significant vertical wind shear and they were probably the reason why the stronger thunderstorms were occurring east of the center of circulation.

Tropical Storm Gilma will move through an environment unfavorable for intensification during the weekend.  Gilma will move over water where the Sea Surface Temperature is near 28°C.  However, the upper level trough will continue to produce significant vertical wind shear.  Gilma is likely to weaken to a depression and it could dissipate if the upper level winds blow the top of the circulation east of the low level center.

Tropical Storm Gilma will move south of a subtropical high pressure system over the Eastern North Pacific.  The strong wind shear will mean that Gilma will be steered by the winds lower in the atmosphere.  Those winds will push Gilma in a general westerly or west-northwesterly direction.

Fabio Strengthens to a Hurricane South of Baja California

Former Tropical Storm Fabio strengthened into a hurricane Monday morning as it moved south of Baja California.  At 11:00 a.m. EDT on Monday the center of Hurricane Fabio was located at latitude 12.8°N and longitude 110.9°W which put it about 700 miles (1125 km) south of the southern tip of Baja California.  Fabio was moving toward the west-northwest at 9 m.p.h. (15 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 989 mb.

The inner core of Hurricane Fabio exhibited signs of greater organization on Monday morning.  Microwave satellite imagery provided evidence of a rainband wrapping around the southern and eastern sides of the center of circulation.  There were intermittent signs that an eye could be forming at the center of circulation.  Several bands of showers and thunderstorms were revolving around the core of the circulation.  The strongest thunderstorms were occurring in bands south and east of the center of Hurricane Fabio.  The bands north and west of the center were weaker, which may indicate that there was some drier air in those parts of the circulation.  Thunderstorms near the core of Fabio were generating upper level divergence which was pumping mass away from the hurricane in all directions.

Hurricane Fabio will be moving through an environment that is very favorable for intensification.  Fabio will move over water where the Sea Surface Temperature is near 28.5°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  It will continue to strengthen and it could intensify rapidly once an eye forms and persists.  Fabio is forecast to strengthen to a major hurricane on Tuesday.

Hurricane Fabio is moving south of a subtropical ridge which is steering the hurricane toward the west-northwest.  The west-northwesterly motion is forecast to continue during the next several days.  On its anticipated track Hurricane Fabio will move away from Baja California.

Tropical Storm Fabio Develops West of Mexico

Tropical Storm Fabio developed west of Mexico on Sunday.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Fabio was located at latitude 12.0°N and longitude 107.4°W which put it about 770 miles (1240 km) south-southeast of the southern tip of Baja California.  Fabio was moving toward the west-northwest at 13 m.p.h. (20 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.

The circulation of Tropical Storm Fabio was still organizing.  There was a broad low level center of circulation, but it did not have a well developed inner core.  Multiple bands of showers and thunderstorms were revolving around the broad low level center.  The storms in the rainbands were generating some upper level divergence which was starting to pump mass away from the tropical storm.

Tropical Storm Fabio will move through an environment that is very favorable for intensification.  Fabio will move over water where the Sea Surface Temperature is near 28.5°C.  An upper level ridge northeast of Tropical Storm Fabio will produce easterly winds which will blow toward the top of the circulation.  However, the wind speed will be similar at all levels and there will not be much vertical wind shear.  Tropical Storm Fabio will continue to intensify in the favorable environment.  Once a primary rainband wraps around the center of circulation, an inner core will develop.  Tropical Storm Fabio could intensify rapidly when an eye starts to form.  Fabio could strengthen into a major hurricane in two or three days.

Tropical Storm Fabio was moving south of a subtropical ridge which was steering the tropical storm toward the west-northwest.  A general west-northwesterly motion is expected to continue during the next few days.  On its anticipated track the center of Tropical Storm Fabio will pass well to the south of Baja California.

Elsewhere over the Eastern North Pacific Ocean Tropical Depression Emilia continued to weaken over cooler water.  At 11:00 a.m. EDT on Sunday the center of Tropical Depression Emilia was located at latitude 19.3°N and longitude 123.0°W which put it about 880 miles (1415 km) west-southwest of the southern tip of Baja California.  Emilia was moving toward the west-northwest at 12 m.p.h. (19 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 1006 mb.

Tropical Storm Emilia Develops South of Baja California

Tropical Storm Emilia developed south of Baja California on Thursday morning.  At 11:00 a.m. EDT on Thursday the center of Tropical Storm Emilia was located at latitude 14.4°N and longitude 112.4°W which put it about 610 miles (980 km) south-southwest of the southern tip of Baja California.  Emilia was moving toward the west-northwest at 14 m.p.h. (22 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.

The distribution of thunderstorms around Tropical Storm Emilia was asymmetrical.  Most of the showers and thunderstorms were occurring in bands west and north of the center of circulation.  The center was located near the eastern edge of a cluster of thunderstorms.  Bands east of the center consisted of showers and low clouds.  The cluster of storms west of the center of circulation was generating upper level divergence which was pumping mass away to the west and north of the tropical storm.

Tropical Storm Emilia will move through an environment somewhat favorable for intensification during the next day or two.  Emilia will move over water where the Sea Surface Temperature is near 28°C.  An upper level ridge centered near the southern tip of Baja California was producing northeasterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear and they were probably the reason why most of the thunderstorms were located west and north of the center of circulation.  The vertical shear is likely to limit intensification during the next 24 hours.  The shear is forecast to decrease on Friday and Tropical Storm Emilia could strengthen faster if that occurs.

The portion of the ridge in the middle troposphere was steering Tropical Storm Emilia toward the west-northwest and that general motion is expected to continue for several more days.  On its anticipated track Emilia will move farther away from the west coast of Mexico.

Tropical Storm Daniel Develops Southwest of Baja California

Tropical Storm Daniel developed southwest of Baja California on Sunday after a relatively quiet week in the tropics.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Daniel was located at latitude 16.0°N and longitude 115.9°W which put it about 615 miles (990 km) southwest of the southern tip of Baja California.  Daniel was moving toward the north 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 1006 mb.

Microwave satellite data indicated that a better organized center of circulation was present inside former Tropical Depression Five-E and the National Hurricane Center designated the system as Tropical Storm Daniel on Sunday morning.  A band of showers and thunderstorms wrapped around the south and east sides of a small tight center of circulation.  Several bands of showers and thunderstorms were revolving around the center.  Bands northwest of the center of circulation consisted primarily of showers and lower clouds.  Storms near the center began to generate upper level divergence which pumped mass away from the tropical storm.

Tropical Storm Daniel will move through an environment favorable for intensification for about another 24 hours.  Daniel is moving over water where the Sea Surface Temperature is near 27°C.  Tropical Storm Daniel will move over cooler water in about a day or so.  There is an upper level low northwest of Daniel.  The low is generating southerly winds which are blowing toward the top of the tropical storm.  Those winds are causing moderate vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Storm Daniel could intensify a little more during the next 24 hours, but Daniel is likely to weaken when it moves over cooler water.

The upper low northwest of Tropical Storm Daniel was steering the tropical storm toward the north.  The upper low is moving toward the west.  Tropical Storm Daniel if forecast to turn more toward the northwest on Monday as it moves around the western side of the upper low.  When Daniel moves over cooler water the clouds will not grow as tall and the tropical storm will be steered by the winds lower in the atmosphere.  The subtropical high over the Pacific Ocean is forecast to steer Daniel more toward the west later next week after the tropical storm weakens.