Tag Archives: Central Pacific

Hurricane Hector Prompts Tropical Storm Warning for Hawaii

The imminent approach of Hurricane Hector prompted the issuance of a Tropical Storm Warning for Hawaii County.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Hector was located at latitude 16.6°N and longitude 150.7°W which put it about 370 miles (590 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 130 m.p.h. (215 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 952 mb.

The circulation of Hurricane Hector remains very well organized and it seems to have reached an equilibrium with its environment.  There is a circular eye at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that rings of storms.  Several bands of showers and thunderstorms are revolving around the core of Hurricane Hector.  Storms around the core were generating well developed upper level divergence was pumping mass away from the hurricane.  Winds to hurricane force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 115 miles (185 km) from the center.

Hurricane Hector will remain in a favorable 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.  Hurricane Hector will remain a strong hurricane for the next few days.

Hurricane Hector will move south of the subtropical ridge over the Central Pacific Ocean.  The ridge will steer Hector in a general westerly direction for several more days.  On its anticipated track the center of Hurricane Hector will pass south of Hawaii.  However, rainbands on the north side of Hector could bring winds to tropical storm force to the Big Island of Hawaii, which is why the Tropical Storm Warning was issued for Hawaii County.

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.

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.