Tag Archives: Hilo

Hurricane Felicia and Tropical Storm Guillermo Weaken

Both Hurricane Felicia and Tropical Storm Guillermo weakened on Monday morning. At 11:00 a.m. EDT on Monday the center of Hurricane Felicia was located at latitude 16.3°N and longitude 132.3°W which put it about 1515 miles (2435 km) east of Hilo, Hawaii. Felicia was moving toward the west at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 990 mb.

Hurricane Felicia weakened rapidly on Monday morning. Felicia moved over water where the Sea Surface Temperatures was near 26°C. The air over the cooler water was also drier. When the drier air entered the small circulation around Hurricane Felicia, thunderstorms in the eyewall and in the rainbands weakened. The eye at the center of Felicia filled with lower clouds. Many of the bands consisted primarily of showers and lower clouds. The strongest thunderstorms were occurring in a small area east of the center of circulation. Winds to hurricane force extended out 15 miles (25 km) from the center. Winds to tropical storm force extended out 45 miles (75 km) from the center of circulation.

Hurricane Felicia will continue to weaken during the next several days. Felicia will move over water where the Sea Surface Temperatures are near 26°C. It will continue to be an environment where the air is relatively dry, which will inhibit the formation of thunderstorms. An upper level trough near Hawaii will produce southwesterly winds that will blow across the top of Felicia. Those winds will cause moderate vertical wind shear and the wind shear will cause Felicia to weaken faster. Hurricane Felicia could weaken to a tropical depression by Tuesday night.

Hurricane Felicia will move south of a subtropical high pressure system over the Eastern North Pacific Ocean. The high will steer Felicia toward the west during the next several days. On its anticipated track the remnants of Hurricane Felicia could pass south of Hawaii at the end of the week.

Elsewhere over the Eastern North Pacific Ocean, Tropical Storm Guillermo also weakened on Monday morning. At 11:00 a.m. EDT on Monday the center of Tropical Storm Guillermo was located at latitude 19.1°N and longitude 117.8°W which put it about 575 miles (925 km) west-southwest of the southern tip of Baja California. Guillermo was moving toward the west at 15 m.p.h. (24 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.

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.

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.

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.

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.

Weakening Tropical Storm Erick Passes South of Hawaii

A weakening Tropical Storm Erick was passing south of Hawaii on Friday.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Erick was located at latitude 16.8°N and longitude 157.4°W which put it about 310 miles (505 km) south of Honolulu, Hawaii.  Erick was moving toward the west-northwest at 14 m.p.h. (22 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.

An upper level trough northwest of the Hawaii Islands was producing strong southwesterly winds which were blowing across the top of Tropical Storm Erick.  Those winds were causing strong vertical wind shear, which was causing Erick to weaken quickly.  Most of the thunderstorms were occurring in bands northeast of the center of circulation.  Bands near the center and in other parts of Tropical Storm Erick consisted primarily of showers and lower clouds.  The stronger winds were occurring in the northern half of the circulation.  Winds to tropical storm force extended out about 100 miles (160 km) from the center of circulation.

A Flash Flood Watch was in effect for the Big Island of Hawaii through Saturday morning.  Counterclockwise flow around Tropical Storm Erick was producing southeasterly which were blowing up the slopes on the Big Island.  The enhanced rising will also increase rainfall on those slopes and flash floods could occur in some locations.

Elsewhere, Tropical Storm Flossie was showing signs of strengthening back into a hurricane.  An eye appeared to be forming at the center of Flossie.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Flossie was located at latitude 17.1°N and longitude 137.8°W which put it about 1145 miles (1845 km) east of HIlo, Hawaii.  Flossie was moving toward the west-northwest at 17 m.p.h. (28 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 993 mb.