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Hurricane Douglas Passes Just North of Hawaii

Hurricane Douglas was passing just to the north of the Hawaiian Islands on Sunday night.  At 11:00 p.m. EDT on Sunday night the center of Hurricane Douglas was located at latitude 22.0°N and longitude 157.3°W which put it about 60 miles (95 km) northeast of Honolulu, Hawaii.  Douglas was moving toward the west-northwest at 16 m.p.h. (26 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 989 mb.

Hurricane Warnings were in effect for Oahu, Kauai and Niihau.

The core of Hurricane Douglas exhibited greater organization on Sunday night.  Thunderstorms around the eye at the center of Douglas grew taller as the hurricane moved over warmer water.  Bands of showers and thunderstorms were revolving around the core.  Winds to hurricane force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out 115 miles (185 km) from the center in the northern half of Hurricane Douglas.  Winds to tropical storm force only extended out about 50 miles (80 km) on the southern side of the circulation.  The stronger winds were remaining north of the Hawaiian Islands.  There were reports of localized minor wind damage on some of the islands.

Hurricane Douglas will move around the south side of a subtropical high pressure system over the North Pacific Ocean.  The high will steer Douglas toward the west-northwest during the next several days.  On its anticipated track the core of Hurricane Douglas will pass north of Oahu.  Scattered minor wind damage could occur on Oahu, Kauai and Niihau.  The southern part of the eyewall could come closer to Kauai and the risk for wind damage is greater there.  Winds blowing uphill could enhance rainfall on Oahu, Kauai and Niihau.  Flash Flood Watches were in effect for those islands.

Hurricane Douglas Prompts Hurricane Warning for Oahu

The approach of Hurricane Douglas prompted the issuance of a Hurricane Warning for Oahu on Saturday afternoon.  At 5:00 p.m. EDT on Saturday the center of Hurricane Douglas was located at latitude 19.5°N and 150.1°W which put it about 325 miles (525 km) east of Hilo, Hawaii.  Douglas was moving toward the west-northwest at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 90 m.p.h. (150 km/h) and there were wind gusts to 110 m.p.h. (175 km/h).  The minimum surface pressure was 984 mb.

A Hurricane Warning was in effect for Oahu.  Hurricane Watches were in effect for Hawaii, Maui, Lanai, Molokai and Kahoolawe.  Tropical Storm Warnings were in effect for Hawaii, Maui, Lanai, Molokai and Kahoolawe.  Tropical Storm Watches were in effect for Kauai and Niihau.

Hurricane Douglas weakened gradually on Saturday as it moved over cooler water.  Douglas was moving over water where the Sea Surface Temperature was near 25°C.  As a result of the cooler water, thunderstorms did not grow as high in the atmosphere.  There was still an eye at the center of circulation, but breaks began to appear in the ring of storms around the eye.  Most of the stronger thunderstorms were in the northern half of the circulation.  Bands in the southern half of the circulation consisted mainly of showers and lower clouds.   Winds to hurricane force extended out about 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out about 110 miles (175 km) from the center.

Hurricane Douglas will move around the southern side of a subtropical high pressure system over the North Pacific Ocean.  The high will steer Douglas toward the west-northwest during the next several days.  On its anticipated track Hurricane Douglas will pass north of the Big Island of Hawaii on Sunday morning.  The core of Douglas could pass near Oahu on Sunday night.

Hurricane Douglas will bring gusty winds to the Hawaiian Islands.  The strongest winds could occur on Oahu.  Winds speeds will be greater at higher elevations.  Douglas could drop heavy rain on the sides of the islands where the wind blows up the slopes.  Flash flooding will be possible.

Hurricane Douglas Prompts Watches for Hawaii

Hurricane Douglas prompted the issuance of Hurricane Watches for some of the Hawaiian Islands on Friday afternoon.  At 5:00 p.m. EDT on Friday the center of Hurricane Douglas was located at latitude 17.0°N and longitude 143.5°W which put it about 785 miles (1260 km) east of Hilo, Hawaii.  Douglas was moving toward the west-northwest at 18 m.p.h. (30 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. (225 km/h).  The minimum surface pressure was 967 mb.

Hurricane Watches were issued for Hawaii, Maui, Lanai, Molokai and Kahoolawe.

Hurricane Douglas continued on a track toward the Hawaiian Islands on Friday, which prompted the issuance of Hurricane Watches.  Douglas was weakening slowly as it moved over slightly cooler water.  In addition, Hurricane Douglas appeared to go through an eyewall replacement cycle which may have contributed to the weakening.  Even though it had weakened, Douglas remained a powerful, well organized hurricane.  There was a circular eye 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 showers and thunderstorms were revolving around the core of Hurricane Douglas.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.

Winds to hurricane force extended out 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out 120 miles (195 km) from the center of Douglas.  The Hurricane Intensity Index (HII) for Hurricane Douglas was 20.6.  The Hurricane Size Index (HSI) was 9.9 and the Hurricane Wind Intensity Size Index (HWISI) was 30.5.  Hurricane Douglas was capable of causing localized major damage.

Hurricane Douglas will move through an environment less favorable for major hurricanes during the next several days.  Douglas will move over water where the Sea Surface Temperature is near 25°C.  So, Hurricane Douglas will not be able to extract as much energy from the upper ocean.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  The lack of wind shear will allow Hurricane Douglas to weaken gradually.

Hurricane Douglas will move south of a subtropical high pressure system over the Eastern and Central North Pacific Ocean.  The high will steer Douglas toward the west-northwest.  On its anticipated track Hurricane Douglas will approach Hawaii on Sunday.

Hurricane Douglas Strengthens to a Major Hurricane

Hurricane Douglas strengthened to a major hurricane on Thursday morning.  At 5:00 a.m. EDT on Thursday the center of Hurricane Douglas was located at latitude 13.1°N and longitude 134.7°W which put it about 1470 miles (2365 km) east-southeast of Hilo, Hawaii.  Douglas was moving toward the west-northwest at 17 m.p.h. (28 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 Douglas strengthened rapidly into a major hurricane during the past 24 hours.  A circular eye formed at the center of Douglas.  A ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Hurricane Douglas.  Storms near the core were generating strong upper level divergence which was pumping mass away from the hurricane.  Winds to hurricane force extended out 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out 100 miles (160 km) from the center.

Hurricane Douglas will move through an environment favorable for intensification during the next 12 to 24 hours.  Douglas 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 weak and there will be little vertical wind shear.  Hurricane Douglas could strengthen on Thursday.  Douglas will start to move over slightly cooler water on Friday.  It is likely to weaken slowly once the core of the circulation moves over the cooler water.

Hurricane Douglas will move south of a subtropical high pressure system over the Eastern North Pacific Ocean.  The high will steer Douglas toward the west-northwest during the next few days.  On its anticipated track Hurricane Douglas could approach Hawaii on Sunday.  Watches could be issued for Hawaii later this week.

Tropical Storm Douglas Strengthens Into a Hurricane

Former Tropical Storm Douglas strengthened into a hurricane east of Hawaii on Wednesday morning.  At 11:00 a.m. EDT on Monday the center of Hurricane Douglas was located at latitude 11.8°N and longitude 129.5°W which put it about 1785 miles (2870 km) east-southeast of Hilo, Hawaii.  Douglas was moving toward the west at 15 m.p.h. (24 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 993 mb.

Former Tropical Storm Douglas exhibited more organization on satellite images.  The inner end of a rainband wrapped around the center of circulation and an eye was visible intermittently on satellite images.  Bands of showers and thunderstorms were revolving around the center of Hurricane Douglas.  Storms near the center were generating upper level divergence which was pumping mass away from the hurricane.  Winds to hurricane force extended out 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extended out 80 miles (130 km) from the center.

Hurricane Douglas will move through an environment favorable for intensification during the next several days.  Douglas 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.  Hurricane Douglas will continue to intensify and it could strengthen into a major hurricane.

Hurricane Douglas will move south of a subtropical high pressure system over the Eastern North Pacific Ocean.  The high will steer Douglas toward the west-northwest.  On its anticipated track Hurricane Douglas could approach Hawaii on Sunday.  Watches could be issued for Hawaii later this week when Douglas moves closer.

Tropical Storm Douglas Strengthens Quickly

Tropical Storm Douglas strengthened quickly over the Eastern North Pacific Ocean on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Douglas was located at latitude 12.4°N and longitude 124.2°W which put it about 2110 miles (3390 km) east of Hilo, Hawaii.  Douglas was moving toward the west-southwest at 15 m.p.h. (24 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.

The circulation around Tropical Storm Douglas exhibited much better organization on Tuesday morning.  The inner end of a rainband wrapped around the southern and eastern sides of the center of circulation.  Bands of showers and thunderstorms were revolving around around the center of Douglas.  The strongest bands were in the southern half of Tropical Storm Douglas.  Storms near the center of circulation were generating upper level divergence which was pumping mass away from the tropical storm.  Winds to tropical storm force extended out about 40 miles (65 km) from the center of Douglas.

Tropical Storm Douglas will move through an environment favorable for intensification during the next several days.  Douglas 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 Douglas is likely to intensify into a hurricane during the next 24 hours and it could strengthen into a major hurricane later this week.

Tropical Storm Douglas will move south of a subtropical high pressure system over the Eastern North Pacific Ocean.  The high is likely to steer Douglas toward the west-northwest during the next few days.  On its anticipated track Tropical Storm Douglas could approach Hawaii by late in the weekend.

Elsewhere over the Eastern North Pacific Ocean, Tropical Depression Seven-E weakened over cooler water east of Hawaii.  At 11:00 a.m. EDT on Tuesday the center of Tropical Depression Seven-E was located at latitude 19.3°N and longitude 134.1°W which put it about 1575 miles (2535 km) west of the southern tip of Baja California.  The depression was moving toward west at 13 m.p.h. (20 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 1009 mb.

Two Tropical Depressions Form Over Eastern Pacific

Two tropical depressions formed over the Eastern North Pacific Ocean on Monday.  At 11:00 a.m. EDT on Monday the center of Tropical Depression Seven-E was located at latitude 18.7°N and longitude 130.3°E which put it about 1345 miles (2170 km) west of the southern tip of Baja California.  The depression was moving toward the northwest at 13 m.p.h. (20 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.

At 11:00 a.m. EDT on Monday the center of Tropical Depression Eight-E was located at latitude 13.7°N and longitude 119.8°W which put it about 905 miles (1460 km) southwest of the southern tip of Baja California.  The depression was moving toward the west-southwest 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 1008 mb.

The distribution of thunderstorms around Tropical Depression Seven-E was asymmetrical.  The strongest storms were occurring in bands southwest of the center of circulation.  Bands in other parts of the depression consisted primarily of showers and lower clouds.  The depression was already to moving over water where the Sea Surface Temperature was near 25°C.  It was moving under the southwestern part of an upper level ridge which was producing northeasterly winds.  Those winds were blowing toward the top of the depression and they were causing moderate vertical wind shear.  Cooler water and wind shear were contributing to the asymmetrical distribution of thunderstorms.

Tropical Depression Seven-E is likely to weaken since it will continue to move over cooler water.  The depression will move south of a subtropical high pressure system.  The high will steer the depression toward the west while it weakens.  On its anticipated track the depression will weaken long before it could pose a threat to Hawaii.

The distribution of thunderstorms around Tropical Depression Eight-E is also asymmetrical.  Many of the strongest storms were occurring in bands in the western half of the circulation.  Some thunderstorms began to develop in bands in the eastern half of the depression on Monday morning.  Storms on the western side of the circulation began to generate upper level divergence which pumped mass away from the depression.

Tropical Depression Eight-E will move through an environment favorable for intensification during the next several days.  The depression will move over water where the Sea Surface Temperature is near 29°C.  The upper level ridge over the Eastern North Pacific Ocean will produce northeasterly winds which will blow toward the top of the depression.  Those winds will cause some vertical wind shear, but the shear will have less effect because the depression will be over warmer water.  Tropical Depression Eight-E will strengthen during the next 48 hours and it could intensify into a hurricane.

Tropical Depression Eight-E will move around the southern side of the subtropical high pressure system over the Eastern North Pacific Ocean.  The high will steer the depression toward the west during the next few days.  On its anticipated track the depression will move in the general direction of Hawaii.

Tropical Storm Cristina Starts to Weaken

Tropical Storm Cristina started to weaken on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Cristina was located at latitude 20.6°N and longitude 121.0°W which put it about 730 miles (1175 km) west of the southern tip of Baja California.  Cristina was moving toward the west 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 999 mb.

Tropical Storm Cristina began to weaken on Saturday when it moved over cooler water.  Cristina moved over water where the Sea Surface Temperature was near 24°C.  The circulation around Tropical Storm Cristina was well organized, but the thunderstorms were not as tall,  A thin broken ring of thunderstorms surrounded the center of circulation and the strongest winds were occurring in that ring of storms.  Other bands of showers and thunderstorms were revolving around the center of circulation.  Storms near the center were still generating upper level divergence.  However, the circulation was unable to extract enough energy from the cooler water to maintain the stronger wind speeds.  Winds to tropical storm force extended out about 80 miles (130 km) from the center of circulation.

Tropical Storm Cristina will continue to weaken during the next few days when it moves over water where the Sea Surface Temperature is near 23°C.  Cristina could weaken to a tropical depression by Monday.

Tropical Storm Cristina will move south of a subtropical high pressure system over the Eastern North Pacific Ocean.  The high will steer Cristina toward the west during the next few days.  On its anticipated track Tropical Storm Cristina will move in the general direction of Hawaii while it weakens.

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.