Tag Archives: 11E

Hurricane John Absorbs Ileana, Tropical Storm Kristy Forms

The much stronger and larger circulation of Hurricane John absorbed the smaller and weaker Tropical Storm Ileana south of Baja California on Tuesday morning, while Tropical Storm Kristy formed farther west over the Eastern North Pacific Ocean.  At 5:00 p.m. EDT on Tuesday the center of Hurricane John was located at latitude 18.7°N and longitude 110.5°W which put it about 295 miles (470 km) south of the southern tip of Baja California.  John was moving toward the northwest at 10 m.p.h. (17 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 969 mb.

The circulation of Hurricane John is well organized.  A circular eye is at the center of circulation.  A ring of stronger thunderstorms wraps around the eye.  The strongest storms are in the eastern half of the ring and that is where the strongest winds are occurring.  Several bands of showers and thunderstorms are revolving around the core of Hurricane John.  The strongest bands are south and east of the center of circulation.  The bands north and west of the center are weaker and there is cooler water in that area.  Storms around the core of the circulation are generating strong upper level divergence which is pumping mass away from the hurricane.

Hurricane John will move through an environment favorable for intensification on Wednesday.  John will move over water where the Sea Surface Temperature is near 29°C.  It will move through an area where the upper level winds are weak.  Hurricane John could intensify on lWednesday and it has a chance to strengthen into a major hurricane.  John will start to move over cooler water in 24 to 36 hours and it will start to weaken when that happens.

Hurricane John will move around the western side of a ridge in the middle troposphere.  The ridge will steer John toward the northwest during the next day or two.  On its anticipated track the core of Hurricane John will pass west of Baja California.  Rainbands north of the center of Hurricane John could drop locally heavy rain over parts of Baja California and there will be a risk of flash floods.  Hurricane John could push higher surf along the west coast of Baja California toward southern California.

Elsewhere over the Eastern North Pacific, Tropical Storm Kristy formed southwest of Hurricane John on Tuesday morning.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Kristy was located at latitude 13.7°N and longitude 127.1°W which put it about 1290 miles (2080 km) west-southwest of the southern tip of Baja California.  Kristy was moving toward the west 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.  There is much uncertainty about whether or not the circulation of Tropical Storm Kristy will be affected by the circulation of Hurricane John.

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 Depression Eleven-E Forms West of Mexico

Tropical Depression Eleven-E formed west of Mexico on Friday.  At 11:00 a.m. EDT on Friday the center of Tropical Depression Eleven-E was located at latitude 17.7°N and longitude 109.2°W which put it about 335 miles (535 km) west-southwest of Manzanillo, Mexico.  The depression was moving toward the west-northwest at 15 m.p.h. (24 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 1009 mb.

The circulation of Tropical Depression Eleven-E is not particularly well organized.  The depression does have a distinct center of circulation which can be seen on visible satellite images.  Most of the showers and thunderstorms are occurring in the western half of the circulation.  The rainbands east of the center of circulation are thin and consist mainly of lighter showers.  The thunderstorms west of the center of circulation are generating only a little upper level divergence which is carrying mass to the west of the depression.

Tropical Depression Eleven-E is in an environment that is only marginally favorable for intensification.  The depression is moving over water where the Sea Surface Temperature is near 28.5°C.  So, there is sufficient energy in the upper ocean to support intensification.  However, an upper level ridge centered over northern Mexico is producing strong northeasterly winds which are blowing across the top of the depression.  Those winds are causing significant vertical wind shear.  The shear is probably the reason for the asymmetrical pattern with all of the thunderstorms in the western half of the circulation.  The shear is forecast to continue and if it does, there will be little or no intensification.  If the shear is less, then some intensification could occur.

Tropical Depression Eleven-E is being steered to the west-northwest by the ridge to its north.  A general west-northwesterly motion is forecast to continue for the next several days.  If the vertical wind shear increases and the depression weakens to a low level system, then winds closer to the surface would steer it more toward the west.  On its anticipated track the depression is expected to move away from Mexico.

Tropical Storm Javier Near Southern Tip of Baja California

Tropical Storm Javier moved slowly toward the southern tip of Baja California on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Javier was located at latitude 22.5°N and longitude 109.7°W which put it about 30 miles (50 km) south-southeast of Cabo San Lucas, Mexico.  Javier was moving toward the northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 999 mb.

The government of Mexico has discontinued all Hurricane Warnings and Watches.  A Tropical Storm Warning remains in effect for the portion of the coast from San Evaristo to Cabo San Lazaro.  A Tropical Storm Watch is in effect for the portion of the coast from San Evaristo to Loreto and from Cabo San Lazaro to Puerto San Andresito.

Javier is a small tropical storm.  Winds to tropical storm force only extend out about 60 miles (95 km) from the center of circulation.  The circulation of Tropical Storm Javier weakened during the past few hours.  Data from a NOAA Hurricane Hunter Research aircraft indicated that drier air in the middle levels had been pulled into the circulation of Javier.  The ingestion of the drier air weakened many of the thunderstorms and the wind speed decreased.  In addition an upper level ridge over northern Mexico appears to be causing easterly winds to blow across the top of Javier.  The vertical wind shear is tilting the circulation and the upper levels of Javier are tilted to the west of the surface center.

Tropical Storm Javier is in an environment that is not favorable for intensification.  Javier is over water where the Sea Surface Temperature is near 28°C, but the water west of Baja California is cooler.  The tropical storm is ingesting drier air and it is encountering vertical wind shear.  The proximity of Tropical Storm Javier to Baja California may also cause the terrain to disrupt the circulation.  Tropical Storm Javier may be able to maintain its intensity at times, but it is likely to weaken during the next several days.

Tropical Storm Javier is moving around the western end of a ridge over Mexico which has been steering it toward the northwest.  Since the thunderstorms in Javier are not as tall, it is being steered by winds lower in the atmosphere and those steering currents appear to be weaker.  As a result, Tropical Storm Javier moved much more slowly on Monday night.  When a tropical cyclone moves very close to Baja California, the terrain has an impact on the structure of the storm and its ultimate motion.  It is possible that the upper and lower portions of Tropical Storm Javier’s circulation could be sheared apart.  If that happens, the lower portion of the circulation could drift slowly along the west coast of Baja California.  The middle and upper portions of the circulation could be pulled north into the southwestern U.S. by an upper level trough off the west coast of the U.S.

The primary risks posed by Tropical Storm Javier are locally heavy rainfall and flash floods.  Steep terrain in parts of Baja California exacerbate the flood risk in those areas.  It is possible that some moisture associated with Tropical Storm Javier could be pulled into the southwestern U.S. later this week.  If that happens, the moisture will enhance rainfall over parts of Arizona and surrounding states.

Tropical Storm Javier Forms and Heads for Baja California

Tropical Storm Javier formed west of Mexico on Sunday and headed for Baja California.  At 11:00 p.m. EDT the government of Mexico issued Hurricane Warnings and Hurricane Watches for part of Baja California.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Javier was located at latitude 20.6°N and longitude 107.7°W which put it about 210 miles (340 km) southeast of Cabo San Lucas, Mexico.  Javier was moving to the 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 999 mb.

The government of Mexico has issued a Hurricane Warning for the portion of the coast from Cabo San Lucas to Todos Santos.  A Hurricane Watch and a Tropical Storm Warning has been issued for the portions of the coast from Todos Santos to Cabo San Lazaro and from Cabo San Lucas to Los Barriles.  A Tropical Storm Warning has been issued for the portion of the coast from Los Barriles to San Evaristo.  A Tropical Storm Watch has been issued for the portion of the coast from San Evaristo to Loreto.

Part of the middle and upper level structure associate with Tropical Storm Earl moved westward across Mexico and interacted with a surface trough of low pressure near the west coast of Mexico.  The middle and upper rotation was transported to the surface and a small low pressure system formed southwest of Manzanillo, Mexico.  The system was originally designated Tropical Depression 11-E early on Sunday.  A weather station at Manzanillo reported a wind from the southeast at 46 m.p.h. (74 km/h) at 11:00 a.m. EDT on Sunday and the National Hurricane Center upgraded the system to Tropical Storm Javier.

Javier is a small tropical storm and the circulation is still organizing.  The tropical storm force winds are occurring within 100 miles (160 km) of the center of Tropical Storm Javier.  Most of the thunderstorms are in the western western half of the tropical storm and many are located close to the center of circulation.  The thunderstorms near the center of Javier are generating upper level divergence but it is primarily moving away to the west of the tropical storm.

Tropical Storm Javier is in an environment that is somewhat favorable for intensification.  It is moving over water where the Sea Surface Temperature (SST) is near 30°C.  An upper level ridge centered near Texas is producing easterly winds that are blowing over the top of Javier.  The easterly winds are causing some vertical wind shear and they are inhibiting upper level divergence to the east of Javier.  Tropical Storm Jaiver may also be drawing in some drier air from Mexico, since it is close to the coast.  The wind shear and drier air will inhibit the rate of intensification, but Tropical Storm Javier should be able to extract enough energy from the warm SSTs to intensify.

Tropical Storm Javier is moving around the western end of the upper level ridge centered near Texas.  Clockwise flow around that ridge is steering Javier toward the west-northwest.  As Javier nears the western end of the ridge, it will turn more toward the north.  On its anticipated track Tropical Storm Javier could approach the southern tip of Baja California by late Monday.

Tropical Storm Javier could do some wind damage, but the primary risks will be locally heavy rainfall and flash flooding.  Tropical Storm Javier could increase the flow of moist air over the southwestern U.S. later this week and it could enhance the normal August thunderstorm activity in that region.