Category Archives: Eastern and Central Pacific

TCs between Mexico and Hawaii

Tropical Storm Lorena Forms, Watch Issued for Mexico

Tropical Storm Lorena formed south of Mexico on Tuesday and a Tropical Storm Watch was issued for a portion of the coast.  At 2:00 p.m. EDT on Tuesday the center of Tropical Storm Lorena was located at latitude 13.9°N and longitude 100.4°W which put it about 275 miles (440 km) south-southeast of Zihuatanejo, Mexico.  Lorena was moving toward the northwest at 15 m.p.h. (24 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 1004 mb.

A Tropical Storm Watch was issued for the portion of the coast from Zihuatanejo to Cabo Corrientes, Mexico.

A distinct low level center of circulation formed in a cluster of thunderstorms south of Mexico on Tuesday and the National Hurricane Center designated the system as Tropical Storm Lorena.  The circulation around Lorena was still organizing.  Bands of showers and thunderstorms were curling around the western side of the center of circulation.  Bands in the eastern half of the circulation consisted primarily of showers and lower clouds.  An upper level ridge over Mexico was producing northeasterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear and they may have been the reason why the bands were stronger in the western half of  Tropical Storm Lorena.

Tropical Storm Lorena will move through an environment favorable for intensification during the next several days.  Lorena will move over water where the Sea Surface Temperature is near 30°C.  The upper level ridge will continue to cause some vertical wind shear, which will inhibit intensification.  The shear is likely to slow the rate at which Tropical Storm Lorena intensifies.  Lorena could move near the west coast of Mexico.  If the center moves near the coast, then the circulation could draw some drier air into the tropical storm.  The drier would likely cause Tropical Storm Lorena to weaken.  If the center of Lorena remains west of the coast of Mexico, then it could strengthen into a hurricane later this week.

A ridge over Mexico will steer Tropical Storm Lorena toward the northwest during the next few days.  On its anticipated track the center of Tropical Storm Lorena could be near the west coast of Mexico by Wednesday night.  That is the reason the government of Mexico issued a Tropical Storm Watch for that portion of the coast.  Lorena could approach Baja California in four or five days.

Elsewhere over the Eastern North Pacific Ocean, Hurricane Kiko was weakening slowly well east of Hawaii and Tropical Depression Fourteen-E developed south of Baja California.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Kiko was located at latitude 17.0°N and longitude 125.0°W which put it about 1060 miles (1705 km) west-southwest of the southern tip of Baja California.  Kiko was moving toward the west-southwest at 5 m.p.h. (8 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 987 mb.

At 11:00 a.m. EDT on Tuesday the center of Tropical Depression Fourteen-E was located at latitude 11.9°N and longitude 108.2°W which put it about 720 miles (1235 km) south of the southern tip of Baja California.  it was moving toward the north-northwest at 9 m.p.h. (15 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.

Hurricane Kiko Strengthens to Cat. 4

Hurricane Kiko strengthened to Category 4 on the Saffir-Simpson Scale on Sunday.  At 11:00 a.m. EDT on Sunday the center of Hurricane Kiko was located at latitude 17.0°N and longitude 121.1°W which put it about 835 miles (1340 km) west-southwest of the southern tip of Baja California.  Kiko was moving toward the west at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 950 mb.

The circulation around Hurricane Kiko remained well organized.  A circular eye with a diameter of 24 miles (39 km) was at the center of Kiko.  The eye was surrounded by 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 Hurricane Kiko.  Kiko remained a small hurricane.  Winds to hurricane force extended out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out about 70 miles (110 km).

Hurricane Kiko will move through an environment capable of supporting a major hurricane for another day or two.  Kiko move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the winds are blowing from the east at all levels and there is little vertical wind shear.  Sinking motion on the south side of a subtropical high pressure system north of Kiko could transport some drier air toward the hurricane.  Hurricane Kiko could be near its peak intensity, but it is likely to remain a powerful hurricane for several more days.

The subtropical ridge over the Eastern North Pacific Ocean will steer Hurricane Kiko toward the west during the next several days.  On its anticipated track Kiko will move away from Baja California and in the general direction of Hawaii.

Kiko Rapidly Intensifies Into Hurricane Southwest of Baja California

Former Tropical Storm Kiko rapidly intensified into a hurricane southwest of Baja California on Saturday.  At 5:00 p.m. EDT on Saturday the center of Hurricane Kiko was located at latitude 17.1°N and longitude 119.3°W which put it about 730 miles (1175 km) west-southwest of the southern tip of Baja California.  Kiko was moving toward the west at 12 m.p.h. (19 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 985 mb.

The circulation around Hurricane Kiko strengthened rapidly on Saturday.  A circular eye with a diameter of 24 miles (39 km) developed at the center of Kiko.  The eye was surrounded by 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 Hurricane Kiko.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.  The circulation around Kiko was small, but symmetrical.  Winds to hurricane force extended out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extended out about 70 miles (110 km) from the center.

Hurricane Kiko will move through an environment favorable for intensification during the next day or two.  Kiko will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the winds at all levels are blowing from the east.  So, there will little vertical wind shear.  Hurricane Kiko is will intensify further and it could strengthen into a major hurricane.

Hurricane Kiko will move south of a subtropical ridge over the Eastern North Pacific Ocean.  The ridge will steer Kiko toward the west.  On its anticipated track Hurricane Kiko will move away from Baja California and toward Hawaii.

Tropical Storm Kiko Forms South of Baja California

Tropical Storm Kiko formed south of Baja California on Thursday.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Kiko was located at latitude 16.1°N and longitude 112.2°W which put it about 495 miles (795 km) south-southwest of the southern tip of Baja California.  Kiko was moving toward the west-northwest at 12 m.p.h. (19 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 1004 mb.

A distinct center of circulation developed in a cluster of thunderstorms south of Baja California on Thursday and the National Hurricane Center designated the system as Tropical Storm Kiko.  The circulation around Kiko was still organizing.  The center of circulation was evident on satellite imagery.  Band of showers and thunderstorms were revolving around the center.  Storms near the center of circulation were beginning to generate upper level divergence which was pumping mass away from the tropical storm.  Winds to tropical storm force extended out about 80 miles (130 km) from the center of circulation.

Tropical Storm Kiko will move through an environment favorable for intensification.  Kiko will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Kiko is likely to strengthen into a hurricane.  Kiko could intensify more rapidly once an eye and eyewall form in the inner core of the tropical storm.

Tropical Cyclone Kiko will move south of a subtropical ridge over the Eastern North Pacific Ocean.  The ridge will steer Kiko toward the west-northwest during the next few days.  On its anticipated track Tropical Storm Kiko will move farther away from Baja California.

Tropical Storm Akoni Develops Southeast of Hawaii

Tropical Storm Akoni developed southeast of Hawaii on Thursday.  At 7:00 p.m. EDT on Thursday the center of Tropical Storm Akoni was located at latitude 12.2°N and longitude 144.8°W which put it about 855 miles (1380 km) southeast of Hilo, Hawaii.  Akoni was moving toward the west at 7 m.p.h. (11 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 1003 mb.

More thunderstorms developed near an area of low pressure southeast of Hawaii on Thursday and the Central Pacific Hurricane Center designated it as Tropical Storm Akoni when satellites indicated there were winds to tropical storm force.  The circulation around Tropical Storm Akoni was still organizing.  Bands of showers and thunderstorms were forming.  The strongest rainbands were in the southern half of the circulation.  Bands in the northern half of the circulation were not as strong.  Winds to tropical storm force extended out about 70 miles (110 km) from the center of circulation.

Tropical Storm Akoni will move through an environment favorable for intensification during the next several days.  Akoni will move over water where the Sea Surface Temperature is near 28°C.  It will move southeast of an upper level trough northeast of Hawaii.  The trough will produce southwesterly winds which will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Storm Akoni is forecast to strengthen gradually during the next several days.

Tropical Storm Akoni will move south of a subtropical high pressure system over the eastern and central Pacific Ocean.  The high will steer Akoni toward the west-northwest.  On its anticipated track Tropical Storm Akoni will be south of Hawaii on Sunday.

Elsewhere, Hurricane Juliette was weakening slowly southwest of Baja California.  At 5:00 p.m. EDT on Thursday the center of Hurricane Juliette was located at latitude 21.3°N and 120.8°W which put it about 870 miles (1380 km) west-southwest of the southern tip of Baja California.  Juliette was moving toward the northwest at 12 m.p.h. (19 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 980 mb.

Juliette Rapidly Intensifies Into a Major Hurricane

Hurricane Juliette rapidly intensified into a major hurricane southwest of Baja California on Monday. At 11:00 p.m. EDT on Monday the center of Hurricane Juliette was located at latitude 17.8°N and longitude 114.0°W which put it abou 440 miles (710 km) southwest of the southern tip of Baja California.  Juliette was moving toward the northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (220 km/h).  The minimum surface pressure was 963 mb.

Hurricane Juliette intensified rapidly on Monday as it moved through an environment of warm water and littler vertical wind shear.  An eye developed 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.  Bands of strong thunderstorms increased in the eastern half of the circulation.  Bands in the western half of the circulation contained fewer thunderstorms.  Storms around the core of Juliette generated strong upper level divergence which pumped mass away from the hurricane.  Winds to hurricane force extended out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extended out about 125 miles (200 km) from the center.

Hurricane Juliette will remain in an environment favorable for intensification for another day or so.  Juliette will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the upper level winds are not too strong and there will be little vertical wind shear.  Hurricane Juliette could strengthen further on Tuesday.  Juliette will move over cooler water later this week and it will start to weaken.

Hurricane Juliette will move southwest of a ridge over the southwestern U.S.  The ridge will steer Juliette toward the northwest.  On its anticipated track Hurricane Juliette will remain well west of Baja California.

Tropical Storm Juliette Develops Rapidly South of Baja California

Tropical Storm Juliette developed rapidly south of Baja California on Sunday.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Juliette was located at latitude 14.3°N and longitude 108.8°W which put it about 600 miles (965 km) south of the southern tip of Baja California.  Juliette was moving toward the northwest at 14 m.p.h. (22 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 1000 mb.

The circulation around Tropical Storm Juliette organized very rapidly on Sunday.  The inner end of a rainband wrapped around the center of circulation and a circular eye appeared to be forming at the center of Juliette.  Other bands of showers and thunderstorms were revolving around the core of the circulation.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical storm.  Winds to tropical storm force extended out about 80 miles (130 km) from the center of circulation.

Tropical Storm Juliette will move through an environment very favorable for intensification.  Juliette will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will is little vertical wind shear.  Tropical Storm Juliette is likely to continue to intensify rapidly during the next day or two.  Juliette is likely to strengthen into a hurricane within 12 hours and it could be a major hurricane within 48 hours.

Tropical Storm Ivo Forms South of Baja California

Tropical Storm Ivo formed south of Baja California on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Ivo was located at latitude 15.8°N and longitude 109.5°W which put it about 490 miles (790 km) south of the southern tip of Baja California.  Ivo was moving toward the west-northwest at 20 m.p.h. (32 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 1004 mb.

A distinct low level center of circulation developed in a low pressure system south of Baja California on Wednesday and the National Hurricane Center designated the system as Tropical Storm Ivo.  A band of thunderstorms wrapped around the western and southern parts of the center of circulation and satellite sensors indicated that winds to tropical storm force were occurring in the band.  Other bands of thunderstorms developed in the western half of Tropical Storm Ivo.  Bands in the eastern half of the circulation consisted primarily of showers and lower clouds.  Thunderstorms near the center of Ivo began to generate upper level divergence which was pumping mass away from the tropical storm.

Tropical Storm Ivo will move through an environment favorable for intensification during the next 36 to 48 hours.  Ivo will move over water where the Sea Surface Temperature is near 29°C.  It will move south of an upper level ridge that stretches from west of California to northern Mexico.  The ridge will produce easterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, which could slow the rate at which Tropical Storm Ivo intensifies. However, the shear will not be strong enough to prevent intensification and Ivo could strengthen into a hurricane within 36 hours.  Tropical Storm Ivo will start to move over cooler water when it moves west of Baja California and that will cause it to weaken during the weekend.

The ridge will steer Tropical Storm Ivo toward the northwest during the next several days.  On its anticipated track Tropical Storm Ivo will move west of Baja California.  The primary impact of Ivo will be to generate waves which will reach the west coast of Baja California and southern California.

Tropical Storm Henriette Forms Southwest of Baja California

Tropical Storm Henriette formed southwest of Baja California on Monday.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Henriette was located at latitude 19.7°N and longitude 112.2°W which put it about 265 miles (430 km) southwest of the southern tip of Baja California.  Henriette was moving toward the west-northwest at 12 m.p.h. (19 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 Henriette was highly asymmetrical.  Most of the thunderstorms were occurring southwest of the center of circulation.  Bands in other parts of the circulation consisted primarily of showers and lower clouds.  Tropical Storm Henriette was south of a narrow upper level ridge.  The ridge was producing northeasterly winds which were blowing across the top of Henriette.  Those winds were causing strong vertical wind shear and they were the cause of the asymmetrical distribution of thunderstorms.

Tropical Storm Henriette will be moving through a region that will be mostly unfavorable for intensification.  Henriette will move over water where the Sea Surface Temperature is near 28.5°C.  So, there will be sufficient energy in the upper ocean to support intensification.  However, the upper level ridge will continue to cause strong vertical wind shear which will prevent intensification.  Tropical Storm Henriette is likely to weaken in a day or two when it moves over colder water.

Tropical Storm Henriette will move south of a subtropical ridge over the Eastern North Pacific Ocean.  The ridge will steer Henriette toward the west-northwest during the next several days.  On its anticipated track Tropical Storm Henriette will move farther away from Baja California.

Tropical Storm Gil Forms Over Eastern North Pacific

Tropical Storm Gil formed over the Eastern North Pacific Ocean on Saturday.  A scatterometer onboard a satellite found winds to tropical storm force northeast of the center of former Tropical Depression Eight-E and the National Hurricane Center designated the system as Tropical Storm Gil.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Gil was located at latitude 15.0°N and longitude 122.4°W which put it about 980 miles (1580 km) west-southwest of the southern tip of Baja California.  Gil was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to about 50 m.p.h. (80 km/h).  The minimum surface pressure was 1006 mb.

The circulation around Tropical Storm Gil was asymmetrical.  There was a distinct low level center of circulation which was visible on satellite imagery.  However, the stronger thunderstorms were occurring east of the center of circulation.  Bands in the western half of Gil consisted primarily of showers and lower clouds.  An upper level trough south of California was producing strong westerly winds which were blowing across the top of the circulation.  The winds were causing strong vertical wind shear and they were contributing to the asymmetrical distribution of thunderstorms.  Tropical storm force winds were occurring within 80 miles (130 km) of the center of Tropical Storm Gil only in the northeastern quadrant of of the circulation.

Tropical Storm Gil will move through an environment only marginally favorable for intensification.  Gil will move over water where the Sea Surface Temperature is near 27°C.  However, the upper level trough will continue to cause significant vertical wind shear.  The strong vertical wind shear will inhibit intensification of Tropical Storm Gil.  Gil could weaken to a tropical depression if the shear increases.

Tropical Storm Gil will move south of a subtropical ridge over the Eastern North Pacific Ocean.  The ridge will steer Gil in a westward direction during the next several days.  On its anticipated track, Tropical Storm Gil will move farther away from Mexico.

Elsewhere over the Central Pacific Ocean, strong vertical wind shear was weakening Tropical Storm Erick and Tropical Storm Flossie.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Erick was located at latitude 17.3°N and longitude 163.9°W which put it about 480 miles (770 km) southwest of Honolulu, Hawaii.  Erick was moving toward the west at 13 m.p.h. (20 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.

At 5:00 p.m. EDT on Saturday the center of Tropical Storm Flossie was located at latitude 18.8°N and longitude 144.5°W which put it about 695 miles (1115 km) east of Hilo, Hawaii.  Flossie 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 1003 mb.