Tag Archives: Hawaii

Tropical Storm Boris Develops East-Southeast of Hawaii

Tropical Storm Boris developed east-southeast of Hawaii on Thursday afternoon.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Boris was located at latitude 11.2°N and longitude 137.1°W which put it about 1330 miles (2145 km) east-southeast of Hilo, Hawaii.  Boris 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.

More thunderstorms developed Thursday afternoon near a low pressure system southeast of Hawaii that was previously designated as Tropical Depression Three-E.  A scatterometer on board a satellite detected winds to 40 m.p.h. (65 km) near the center of the low pressure system and the National Hurricane Center designated the system as Tropical Storm Boris.  A band of showers and thunderstorms wrapped around the southern and eastern sides of the center of circulation and the strongest winds were occurring in that band of storms.  A few other short bands of showers and thunderstorms developed in the eastern half of Boris.  Bands in the western half of the circulation consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out about 50 miles from the center of circulation.

Tropical Storm Boris will move through an environment marginally favorable for intensification during the next 12 to 24 hours.  Boris will move over water where the Sea Surface Temperature is near 26.5°C.  A large upper level trough between Hawaii and the West Coast of the U.S. will produce southwesterly winds which will blow toward the top of the circulation.  Those winds will cause moderate vertical wind shear and the shear will limit intensification.  In addition, there is drier air north and west of Tropical Storm Boris.  Boris could intensify during the next 12 hours in spite of the moderate vertical wind shear and drier air.  However, Tropical Storm Boris will move into a region where the upper level winds are stronger during the weekend.  When the vertical wind shear increases, Boris will weaken.

Tropical Storm Boris will move south of a subtropical high pressure system over the Eastern North Pacific Ocean.  The will steer Boris toward the west-northwest during the next 24 hours.  When Tropical Storm Boris weakens during the weekend, it will be steered by winds closer to the surface.  Those winds will steer Boris toward the west.  On its anticipated track the weakening Tropical Storm Boris will pass southeast of Hawaii.

One-E Becomes Earliest East Pacific Tropical Depression

Tropical Depression One-E became Saturday the earliest tropical depression for form over the Eastern North Pacific Ocean during the satellite era which began in 1966.  The previous date of the earliest formation over that region was May 9, 2017 when a depression formed that would ultimately strengthen into Tropical Storm Adrian.  At 11:00 a.m. EDT on Saturday the center of Tropical Depression One-E was located at latitude 14.1°N and longitude 116.1°E which put it about 730 miles (1175 km) southwest of the southern tip of Baja California.  The depression 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 were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1006 mb.

More thunderstorms developed near the center of a low pressure system previously designated as Invest 90E southwest of Baja California on Saturday morning and National Hurricane Center designated the system as Tropical Depression One-E.  Tropical Depression One-E is the first tropical depression to form over the Eastern North Pacific Ocean during the month of April in the satellite era .  The distribution of thunderstorms around the depression was asymmetrical.  Many of the stronger thunderstorms were occurring in bands in the southern half of the circulation.  Bands in the northern half of the circulation consisted primarily of showers and lower clouds.  The southern half of the circulation was over warmer Sea Surface Temperatures, which may have contributed to the development of thunderstorms in that part of the tropical depression.

Tropical Depression One-E will move through an environment somewhat favorable for intensification during the next 24 hours.  The depression will move over water where the Sea Surface Temperature is near 26.5°C.  It will move under the western end of an upper level ridge over the Eastern North Pacific Ocean.  The ridge will produce southerly winds which will blow toward the top of the circulation.  Those winds will cause moderate vertical wind shear and they will inhibit intensification.  Conditions could be favorable enough to allow Tropical Depression One-E to strengthen into a tropical storm during the next 24 hours.  The depression will move over cooler Sea Surface Temperatures later on Sunday, which will cause it to weaken.

Tropical Depression One-E will move around the western end of a high pressure system over the Eastern North Pacific Ocean during the next 24 hours.  The high will steer the depression toward the northwest on Saturday.  A second high pressure system over the North Pacific Ocean will block the northward movement of the depression later on Sunday.  The second high will steer the depression more toward the west later in the weekend.

Possible Tropical Development

A tropical cyclone could possibly form south of Baja California during the next few days.  The system has been designated as Invest 90E.  At 2:00 p.m. EDT on Thursday the center of Invest 90E was located at latitude 10.2°N and longitude 111.7°W which put it about 870 miles (1405 km) south of the southern tip of Baja California.  It was moving toward the west at 9 mp.h. (15 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 1008 mb.

An area of thunderstorms has persisted south of Baja California for the past several days.  More thunderstorms developed on Thursday.  Visible satellite images indicated that the thunderstorms were organizing into bands and there was some counterclockwise rotation of the bands around a center of circulation.  There appeared to be a low level center of circulation.  However, there were not enough thunderstorms around the center of circulation for the system to be classified as a tropical cyclone.

Invest 90E will move through an environment somewhat favorable for the formation of a tropical cyclone during the next 48 hours.  it will move over water where the Sea Surface Temperature is near 29°C.  Invest 90E will move under the western end of an upper level ridge over the Eastern North Pacific Ocean.  The ridge will produce southerly winds which will blow across the top of the system.  Those winds will cause moderate vertical wind shear and they will inhibit the formation of a tropical cyclone.   If the strength of the upper level wind diminishes slightly, then the environment will become more favorable for the formation of a tropical cyclone.  The National Hurricane Center indicated that the probability of formation of a tropical cyclone during the next two days was 40%.

Invest 90E will move around the western end of a high pressure system over the far Eastern North Pacific Ocean during the next several days.  The high will steer the system toward the northwest.  On its anticipated track Invest 90E will remain well to the southwest of Baja California during the weekend.

Tropical Storm Octave Forms over Eastern North Pacific

Tropical Storm Octave formed over the Eastern North Pacific Ocean on Thursday evening.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Octave was located at latitude 9.8°N and longitude 127.2°W which put it about 1455 miles (2345 km) southwest of the southern tip of Baja California.  Octave was moving toward the west at 3 m.p.h. (5 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.

More thunderstorms formed near the center of a small low pressure system between Mexico and Hawaii and the National Hurricane Center designated the system as Tropical Storm Octave.  The circulation around Octave exhibited more organization and tropical characteristics on Thursday evening.  There was a distinct low level center of circulation with thunderstorms.  Several bands of showers and thunderstorms were revolving around the center.  Storms near the center generated upper level divergence which pumped mass away from the tropical storm.  The circulation around Tropical Storm Octave was small.  Winds to tropical storm force only extended out 35 miles (55 km) from the center of circulation.

Tropical Storm Octave will move through an environment mostly favorable for intensification.  Octave will move over water where the Sea Surface Temperature is 28°C.  It will be in a region where the upper level winds are weak and there will be little vertical wind shear.  However, there appears to be drier air north of Tropical Storm Octave.  If the circulation pulls drier air into the core of Octave, then thunderstorms around the center would weaken which would make intensification unlikely.  Tropical Storm Octave could strengthen a little during the next 24 hours.

Tropical Storm Octave will be in a region where the winds at the steering level are weak.  Octave is forecast to move little during the next few days.  Because Tropical Storm Octave will not move much, it will remain well away from any land area.

Tropical Storm Ema Forms Southwest of Hawaii

Tropical Storm Ema formed southwest of Hawaii on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Ema was located at latitude 21.1°N and longitude 163.9°W which put it about 245 miles (395 km) southeast of French Frigate Shoals.  Ema was moving toward 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 1003 mb.

A Tropical Storm Watch has been issued for the Papahanaumokuakea Marine National Monument from Nihoa to French Frigate Shoals to Maro Reef.

A distinct low level center of circulation formed in a small area of low pressure southwest of Hawaii on Saturday morning and the Central Pacific Hurricane Center designated the system as Tropical Storm Ema.  The circulation around Tropical Storm Ema was very small.  Winds to tropical storm force extended out 45 miles (75 km) from the center of circulation.  Several short bands of showers and thunderstorms developed around the center of Ema.  Storms near the center began to generate upper level divergence which pumped mass away from the tropical storm.

Tropical Storm Ema will move through an environment marginally favorable for intensification during the next 12 to 24 hours.  Ema will move over water where the Sea Surface Temperature is near 28°C.  An upper level trough west of Hawaii will produce southerly winds which will blow toward the top of the circulation.  Those winds will cause moderate vertical wind shear which inhibit the intensification of Tropical Storm Ema.  Ema could strengthen a little during the next 12 to 24 hours.  The upper level trough will produce stronger southwesterly winds on Sunday and the wind shear will increase.  Stronger wind shear will weaken Tropical Storm Ema in a day or so.  The upper level winds could blow the top half of Ema north of the low level circulation and the tropical storm could weaken very quickly if that happens.

The upper level trough will steer Tropical Storm Ema toward the north during the next 12 hours or so.  If the wind shear separates the upper and lower parts of the tropical storm, the low level center will be steered by winds closer to the surface.  Clockwise flow around a subtropical high pressure system centered northeast of Hawaii could steer Tropical Storm Ema more toward the northwest later on Sunday.

Tropical Storm Lorena Moves Toward Baja California

Tropical Storm Lorena moved toward Baja California on Thursday night after brushing the west coast of Mexico earlier in the day.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Lorena was located at latitude 22.3°N and longitude 107.7°W which put it about 145 miles (235 km) east-southeast of Cabo San Lucas, Mexico.  Lorena was moving toward the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 994 mb.

A Hurricane Warning was in effect for the portion of the coast from La Paz to Puerto Cortes, Mexico.  A Hurricane Watch was in effect from La Paz to San Evaristo, Mexico.  Tropical Storm Watches were in effect from San Evaristo to Loreto and from Puerto Cortes to Puerto San Evaristo.

When the center of former Hurricane Lorena passed near the west coast of Mexico, the eastern part of the circulation passes over mountains.  The mountains disrupted the flow of air and some drier air was pulled into the hurricane.  The disruption and drier air weakened the inner core of the circulation and caused Lorena to weaken to a tropical storm.  The inner core was beginning to redevelop on Thursday evening.  More thunderstorms were forming near the center of circulation and other thunderstorms were occurring in bands in the eastern half of the circulation.  Winds to tropical storm force extended out about 70 miles (110 km) from the center of circulation.

Tropical Storm Lorena will move through an environment favorable for intensification on Friday.  Lorena 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 Storm Lorena is likely to strengthen back into a hurricane on Friday.

Tropical Storm Lorena will move around the western part of a ridge of high pressure over Mexico.  The ridge will steer Lorena toward the northwest.  The circulation of Tropical Storm Lorena will interact with the circulation of Tropical Storm Mario which is southwest of Lorena.  It looked like Lorena was pulling Mario toward the northeast on Thursday night.  However, it is possible that Mario could tug Lorena more toward the west on Friday.  On its anticipated track Tropical Storm Lorena will approach the southern tip of Baja California on Friday afternoon.  Lorena is likely to be a hurricane at that time.

Elsewhere over the Eastern North Pacific Ocean, Tropical Storm Mario was southwest of Lorena and Tropical Storm Kiko was between Baja California and Hawaii.  At 11:00 p.m. EDT the center of Tropical Storm Mario was located at latitude 17.6°N and longitude 110.2°W which put it about 265 miles (590 km) south of the southern tip of Baja California.  Mario was moving toward the northeast at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h (130 km/h).  The minimum surface pressure was 995 mb.

At 11:00 p.m. EDT on Thursday the center of Tropical Storm Kiko was located at latitude 16.6°N and longitude 129.6°W which put it about 1350 miles (2175 km) west-southwest of the southern tip of Baja California.  Kiko was moving toward the northwest at 6 m.p.h. (10 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 1002 mb.

Lorena Strengthens to a Hurricane Near Manzanillo

Former Tropical Storm Lorena strengthened to a hurricane near Manzanillo, Mexico on Wednesday night.  At 11:00 p.m. EDY on Wednesday the center of Hurricane Lorena was located at latitude 18.7°N and longitude 104.7°W which put it 35 miles (55 km) southwest of Manzanillo, Mexico.  Lorena was moving toward the northwest at 12 m.p.h. (19 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 990 mb.

A Hurricane Warning was in effect for the portion of the coast from Punta San Telmo to Cabo Corrientes, Mexico.  A Tropical Storm Warning was in effect for the coast from Cabo Corrientes to Punta Mita, Mexico.

The circulation around Hurricane Lorena exhibited more organization on Wednesday night.  Some satellite images suggested that a small eye might be forming at the center of circulation.  Lorena was a small 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 90 miles (145 km) from the center.

Hurricane 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 29°C.  It will move through a region where the upper level winds are not too strong and there is not likely to be a lot of vertical wind shear.  However, the center of Hurricane Lorena will move very close to the coast of Mexico.  Small hurricanes often draw drier air over the land into their circulations when they move close to the west coast of Mexico.  If Hurricane Lorena draws in drier air, it will weaken even though the rest of the environment is favorable for intensification.  If the center of Lorena moves farther away from the coast, then the hurricane could strengthen.

Hurricane Lorena will move around the western side of a ridge over Mexico.  The ridge will steer Lorena toward the northwest during the next several days.  On its anticipated track, Hurricane Lorena will pass very close to the west coast of Mexico on Thursday.  Hurricane Lorena could drop locally heavy rain and flash floods could occur.  If Hurricane Lorena doesn’t weaken near the coast, it could approach the southern tip of Baja California on Friday.

Elsewhere over the Eastern North Pacific Ocean, Tropical Storms Kiko and Mario strengthened on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Kiko was located at latitude 15.8°N and longitude 127.8°W which put it about 1265 miles (2035 km) west-southwest of the southern tip of Baja California.  Kiko was moving toward the west at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 998 mb.

At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Mario was located at latitude 15.4°N and longitude 112.2°W which put it about 540 miles 9870 km) south-southwest of the southern tip of Baja California.  Mario was moving toward the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 998 mb.

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.