Monthly Archives: August 2024

Typhoon Shanshan Continues to Strengthen

Typhoon Shanshan continues to strengthen over the Western North Pacific Ocean south of Japan on Sunday.  At 11:00 p.m. EDT on Sunday the center of Typhoon Shanshan was located at latitude 27.3°N and longitude 133.5°E which put the center about 350 miles (565 km) south-southeast of Kagoshima, Japan.  Shanshan was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 968 mb.

Typhoon Shanshan strengthened gradually on Sunday as it moved over the Western North Pacific Ocean south of Japan.  A large circular eye was present at the center of Shanshan’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Typhoon Shanshan.  Storms near the core of Shanshan’s circulation generated more upper level divergence that pumped mass away from the typhoon.  The removal of more mass caused the surface pressure to decrease.

The size of the circulation around typhoon Shanshan increased slightly on Sunday.  Winds to typhoon force extended out 35 miles (55 km) from the center of Shanshan’s circulation.  Winds to tropical storm force extended out 145 miles (230 km) from the center of Typhoon Shanshan.

The Hurricane Intensity Index (HII) for Typhoon Shanshan was 13.9.  The Hurricane Size Index (HSI) was 11.7 and the Hurricane Wind Intensity Size Index (HWISI) was 25.6.

Typhoon Shanshan will move through an environment that will be favorable for intensification during the next 24 hours.  Shanshan will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the northern periphery of an upper level low south of Japan.  The upper level low will produce easterly winds that will blow toward the top of Shanshan’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Typhoon Shanshan will intensify during the next 24 hours.

Typhoon Shanshan will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Shanshan toward the northwest during the next 24 hours.  On its anticipated track, Typhoon Shanshan will move closer to Kyushu and Shikoku.  Shanshan could approach southwestern Japan in 48 hours.  Shanshan could be a strong typhoon when it approaches Japan.

 

Hone Strengthens to a Hurricane South of Hawaii

Former Tropical Storm Hone strengthened to a hurricane south of Hawaii on Saturday night.  At 5:00 a.m. EDT on Sunday the center of Hurricane Hone was located at latitude 18.2°N and longitude 155.3°W which put the center about 105 miles (165 km) south of Hilo, Hawaii.    Hone was moving toward the west 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 991 mb.

A Tropical Storm Warning was in effect for Hawaii County (the Big Island).

Former Tropical Storm Hone strengthened to a hurricane during Saturday night as the center of Hone moved just south of South Point, Hawaii.  A circular eye with a diameter of 30 miles formed at the center of Hone’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storm,  Bands of showers and thunderstorms were revolving around the center of Hone’s circulation.  Storms near the center of Hone generated more upper level divergence that pumped mass away from the hurricane.  The removal of more mass caused the surface pressure to decrease.

The size of the circulation around Hurricane Hone increased a little during Saturday night.  Winds to hurricane force extended out 20 miles (30 km) in the northern side of Hone’s circulation.  Winds to tropical storm force extended out 130 miles (210 km) from the center of Hurricane Hone.

Hurricane Hone will move through an environment favorable for intensification during the next 24 hours.  Hone will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southern side of an upper level ridge centered west of Hawaii.  The upper level ridge will produce northeasterly winds that will blow toward the top of Hone’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Hurricane Hone is likely to intensify gradually during the next 24 hours.

Hurricane Hone will move around the southern side of a subtropical high pressure system over the Eastern North Pacific and Central Pacific.  The high pressure system will steer Hone toward the west-northwest during the next 24 hours.  On its anticipated track, the center Hurricane Hone will move away from of Hawaii County (the Big Island) on Sunday.

The core of Hurricane Hone where the strongest winds are will pass south of Hawaii County.  Bands in the northern side of Hone’s circulation could bring strong winds to the Big Island.  Electricity outages are likely.  Those bands will also drop heavy rain on parts of Hawaii County.  Heavy rain is likely to cause flash floods in some locations.

A Flood Watch is in effect for Hawaii County.

Elsewhere, Hurricane Gilma intensified to Category 4 on the Saffir-Simpson Scale over the Eastern North Pacific Ocean east of Hawaii.  At 5:00 a.m. EDT on Sunday the center of Hurricane Gilma was located at latitude 18.0°N and longitude 132.5°W which put the center about 1480 miles (2380 km) east of Hilo, Hawaii.  Gilma was moving toward the west-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 949 mb.

 

Typhoon Shanshan Passes West of Iwo To

The center of Typhoon Shanshan passed west of Iwo To on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Typhoon Shanshan was located at latitude 25.4°N and longitude 138.4°E which put the center about 150 miles (240 km) west of Iwo To.  Shanshan was moving toward the northwest 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 974 mb.

Typhoon Shanshan maintained its intensity on Saturday as it moved over the Western North Pacific Ocean west of Iwo To.  Shanshan moved under the eastern side of an upper level low south of Japan.  The upper level low produced southerly winds that blew toward the top of Shanshan’s circulation.  Those winds caused moderate vertical wind shear, and the wind shear prevented intensification of Typhoon Shanshan.

The vertical wind shear also affected the structure of Typhoon Shanshan.  A small circular eye was present at the center of Shanshan’s circulation.  The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Thunderstorms were occurring in bands in the northern side of Typhoon Shanshan.  Bands in the southern part of Shanshan’s circulation consisted primarily of showers and lower clouds.  Storms near the center of Shanshan generated upper level divergence that pumped mass away to the north of the typhoon.  The removal of mass in the upper levels was balanced by the inflow of mass in the lower levels of the atmosphere.  The balance of the outflow and inflow of mass caused the surface pressure to remain steady on Saturday.

Winds to typhoon force extended out 35 miles (55 km) from the center of Typhoon Shanshan.  Winds to tropical storm force extended out 125 miles (200 km) from the center of Shanshan’s circulation.

Typhoon Shanshan will move through an environment that will become more favorable for intensification during the next 24 hours.  Shanshan will move over water where the Sea Surface Temperatures are near 29°C.  It will move farther away from the upper level low south of Japan.  The upper level low will still produce southerly winds that will blow toward the top of Shanshan’s circulation.  However, there will be less vertical wind shear on Sunday.  Typhoon Shanshan is likely to intensify during the next 24 hours.

Typhoon Shanshan will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Shanshan toward the northwest during the next 24 hours.  On its anticipated track, Typhoon Shanshan will move closer to Kyushu and Shikoku.  Shanshan could approach southwestern Japan in 48 hours.  Shanshan could be a strong typhoon when it approaches Japan.

 

Tropical Storm Hone Moves Southeast of Hawaii

Tropical Storm Hone moved southeast of Hawaii on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Hone was located at latitude 17.7°N and longitude 153.2°W which put the center about 185 miles (300 km) southeast of Hilo, Hawaii.   Hone was moving toward the west 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. (120 km/h).  The minimum surface pressure was 1000 mb.

A Tropical Storm Warning was in effect for Hawaii County (the Big Island).

Tropical Storm Hone continued to strengthen gradually on Saturday.  The low level circulation of Tropical Storm Hone remained well organized and very symmetrical.  The inner end of a rainband wrapped around the eastern side of the center of Hone’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Hone.  Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass in the upper levels was nearly balanced by the inflow of mass in the lower levels of the atmosphere.  The balanced transport of mass caused the surface pressure to remain steady.

Even though the low level circulation of Tropical Storm Hone was very symmetrical, the distribution of wind speeds was asymmetrical.  Winds to tropical storm force extended out 125 miles (200 km) in the northern side of Hone’s circulation.  Winds to tropical storm force extended out 80 miles (130 km) in the southern side of Tropical Storm Hone.

Tropical Storm Hone will move through an environment favorable for intensification during the next 24 hours.  Hone will move over water where the Sea Surface Temperatures are near 27°C. It will move under the southern side of an upper level ridge centered west of Hawaii.  The upper level ridge will produce northeasterly winds that will blow toward the top of Hone’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Tropical Storm Hone is likely to intensify gradually during the next 24 hours.

Tropical Storm Hone will move around the southern side of a subtropical high pressure system over the Eastern North Pacific and Central Pacific.  The high pressure system will steer Hone toward the west-northwest during the next 24 hours.  On its anticipated track, the center Tropical Storm Hone will pass just south of Hawaii County (the Big Island) on Saturday night.

Even though the center of Tropical Storm Hone is likely to pass south of Hawaii, it could bring winds to tropical storm force to Hawaii County.  Hone could also produce locally heavy rain.

Elsewhere, Hurricane Gilma churned westward over the Eastern North Pacific Ocean east of Hawaii.  At 5:00 p.m. EDT on Saturday the center of Hurricane Gilma was located at latitude 17.7°N and longitude 130.9°W which put the center about 1585 miles (2555 km) east of Hilo, Hawaii.  Gilma was moving toward the west at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 968 mb.

 

 

 

Shanshan Strengthens to a Typhoon

Former Tropical Storm Shanshan strengthened to a typhoon over the Western North Pacific Ocean south of Iwo To.  At 11:00 p.m. EDT on Friday the center of Typhoon Shanshan was located at latitude 20.5°N and longitude 141.2°E which put the center about 330 miles (535 km) south of Iwo To.  Shanshan was moving toward the north at 14 m.p.h. (22 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 974 mb.

Former Tropical Storm Shanshan strengthened to a typhoon south of Iwo To on Friday.  The inner end of a raindband wrapped around the center of Shanshan’s circulation.  A circular eye formed at the center of Typhoon Shanshan.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Shanshan’s circulation.  Storms near the center of Shanshan generated more upper level divergence that pumped mass away from the typhoon.  The removal of more mass caused the surface pressure to decrease.

Winds to typhoon force extended out 30 miles (50 km) from the center of Typhoon Shanshan.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Shanshan’s circulation.

Typhoon Shanshan will move through an environment favorable for intensification during the next 24 hours.  Shanshan will move over water where the Sea Surface Temperatures are near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Shanshan will intensify during the next 24 hours.

Typhoon Shanshan will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Shanshan toward the north-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Shanshan will be near Iwo To in 24 hours.  Shanshan could approach central Japan in 72 hours.

 

Hone Prompts Tropical Storm Warning for Hawaii County

The potential risk posed by Tropical Storm Hone prompted the issuance of a Tropical Storm Warning for Hawaii County.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Hone was located at latitude 16.9°N and longitude 149.3°W which put the center about 425 miles (685 km) east-southeast of Hilo, Hawaii.  Hone was moving toward the west at 16 m.p.h. (26 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.

A Tropical Storm Warning was in effect for Hawaii County (the Big Island).

Tropical Storm Hone strengthened gradually on Friday.  The low level circulation of Tropical Storm Hone was well developed and very symmetrical.  More thunderstorms developed in the inner end of a rainband that wrapped around the eastern side of the center of Hone’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Hone.  Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm.

Even though the low level circulation of Tropical Storm Hone was very symmetrical, the distribution of winds speeds was asymmetrical.  Winds to tropical storm force extended out 115 miles (185 km) in the northern side of Hone’s circulation.  Winds to tropical storm force extended out 60 miles in the southern side of Tropical Storm Hone.

Tropical Storm Hone will move through an environment favorable for intensification during the next 24 hours.  Hone will move over water where the Sea Surface Temperatures are near 28°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Hone is likely to intensify gradually during the next 24 hours.

Tropical Storm Hone will move around the southern side of a subtropical high pressure system over the Eastern North Pacific and Central Pacific.  The high pressure system will steer Hone toward the west-northwest during the next 24 hours.  On its anticipated track, the center Tropical Storm Hone will pass just south of Hawaii County (the Big Island) on Saturday night.

Even though the center of Tropical Storm Hone is likely to pass south of Hawaii, it could bring winds to tropical storm force to Hawaii County.  Hone could also produce locally heavy rain.

Elsewhere, Hurricane Gilma weakened gradually east of Hawaii.  At 11:00 p.m. EDT on Friday the center of Hurricane Gilma was located at latitude 17.5°N and longitude 128.4°W which put the center about 1750 miles (2820 km) east of Hilo, Hawaii.  Gilma was moving toward the west at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 970 mb.

 

Tropical Storm Hone Forms East-southeast of Hawaii

Tropical Storm Hone formed east-southeast of Hawaii on Thursday afternoon.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Hone was located at latitude 15.9°N and longitude 142.2°W which put the center about 885 miles (1430 km) east-southeast of Hilo, Hawaii.  Hone was moving toward the west-northwest at 14 m.p.h. (22 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.

A low pressure system over the Central Pacific Ocean east-southeast of Hawaii strengthened on Thursday afternoon and the U.S. Central Pacific Hurricane Center designated the system as Tropical Storm Hone.  More thunderstorms developed near the center of Hone’s circulation on Thursday afternoon.  More thunderstorms also formed in bands revolving around the center of Tropical Storm Hone.  Storms near the center of Hone began to generate upper level divergence that pumped mass away from the tropical storm.

The circulation around Tropical Storm Hone was small.  Winds to tropical storm force extended out 20 miles in the northern side of Hone’s circulation.  The winds in the southern part of Tropical Storm Hone were blowing at less than tropical storm force.

Tropical Storm Hone will move through an environment favorable for intensification during the next 24 hours.  Hone will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southern part of an upper level ridge over the Eastern North Pacific and the Central Pacific.  The upper level ridge will produce northeasterly winds that will blow toward the top of Hone’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Storm Hone is likely to intensify gradually during the next 24 hours.

Tropical Storm Hone will move around the southern side of a subtropical high pressure system over the Eastern North Pacific and Central Pacific.  The high pressure system will steer Hone toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Hone will move closer to Hawaii.  Hone could be southeast of Hawaii by Saturday evening.

Gilma Strengthens to a Major Hurricane

Hurricane Gilma strengthened to a major hurricane over the Eastern North Pacific Ocean between Baja California and Hawaii on Thursday morning.   At 5:00 a.m. EDT on Thursday the center of Hurricane Gilma was located at latitude 16.6°N and longitude 124.2°W which put the center about 1025 miles (1650 km) west-southwest of the southern tip of Baja California.  Gilma was moving toward the west-northwest at 6 m.p.h. (10 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 Gilma strengthened to a major hurricane over the Eastern North Pacific Ocean between Baja California and Hawaii on Thursday morning.  A circular eye with a diameter of 17 miles (28 km) was present at the center of Gilma’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Hurricane Gilma.  Storms near the core of Gilma generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The circulation around Hurricane Gilma was symmetrical.  Winds to hurricane force extended out 30 miles (50 km) from the center of Gilma’s circulation.  Winds to tropical storm force extended out 125 miles (200 km) from the center of Hurricane Gilma.

Hurricane Gilma will move through an environment favorable for intensification during the next 24 hours.  Gilma will move over water where the Sea Surface Temperatures are near 28°C. It will move under the southern part of an upper level ridge over the Eastern north Pacific Ocean.  The upper level ridge will produce northeasterly winds that will blow toward the top of Gilma’s circulation.  Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Hurricane Gilma is likely to continue to intensify during the next 24 hours.

Hurricane Gilma will move around the southern side of a subtropical high pressure system over the Eastern North Pacific Ocean.  The high pressure system will steer Gilma slowly toward the west-northwest during the next 24 hours.  On its anticipated track, Hurricane Gilma will move farther away from Baja California.

 

Tropical Storm Shanshan Forms South of Iwo To

Tropical Storm Shanshan formed over the Western North Pacific Ocean south of Iwo To on Wednesday evening.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Shanshan was located at latitude 17.2°N and longitude 141.5°E which put the center about 505 miles (810 km) south of Iwo To.  Shanshan 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 1001 mb.

A low pressure system over the Western North Pacific Ocean south of Iwo To strengthened on Wednesday evening and the Japan Meteorological Agency designated the system as Tropical Storm Shanshan.  The circulation around Tropical Storm Shanshan exhibited more organization on satellite images, but the distribution of thunderstorms was asymmetrical.  Thunderstorms were occurring in bands in the eastern side of Shanshan’s circulation.  Bands in the western side of Tropical Storm Shanshan consisted primarily of showers and lower clouds.  Storms near the center of Shanshan began to generate upper level divergence that pumped mass away from the tropical storm.

The circulation around Tropical Storm Shanshan was small.  Winds to tropical storm force extended out 45 miles (75 km) from the center of Shanshan’s circulation.

Tropical Storm Shanshan will move through an environment favorable for intensification during the next 24 hours.  Shanshan will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southeastern part of an upper level ridge over Japan.  The ridge will produce northerly winds that will blow toward the top of Shashan’s circulation.  Those winds will cause vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Storm Shanshan will intensify during the next 24 hours.  Shanshan is likely to strengthen to a typhoon within 36 hours/

Tropical Storm Shanshan will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Shanshan toward the north-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Shanshan will move closer to Iwo To.  Shanshan could approach Japan in five days.

Gilma Intensifies to a Hurricane

Former Tropical Storm Gilma intensified to a hurricane over the Eastern North Pacific Ocean between Baja California and Mexico on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Hurricane Gilma was located at latitude 16.0°N and longitude 122.8°W which put the center about 965 miles (1555 km) west-southwest of the southern tip of Baja California.  Gilma was moving toward the west at 7 m.p.h. (11 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 983 mb.

Former Tropical Storm Gilma intensified to a hurricane between Baja California and Hawaii on Wednesday morning.  The inner end of a rainband wrapped around the center of Hurricane Gilma.  A circular eye was evident on microwave satellite images of Gilma.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Hurricane Gilma.  Storms near the center of Gilma’s circulation generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The circulation around Hurricane Gilma was more symmetrical on Wednesday morning.  Winds to hurricane force extended out 30 miles (50 km) from the center of Gilma’s circulation.  Winds to tropical storm force extended out 140 miles (220 km) from the center of Hurricane Gilma.

Hurricane Gilma will move through an environment favorable for intensification during the next 24 hours.  Gilma will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southern part of an upper level ridge over the Eastern north Pacific Ocean.  The upper level ridge will produce northeasterly winds that will blow toward the top of Gilma’s circulation.  Those winds will cause some vertical wind shear.  The wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Hurricane Gilma will continue to intensify during the next 24 hours.  Gilma could strengthen to a major hurricane later this week.

Hurricane Gilma will move around the southern side of a subtropical high pressure system over the Eastern North Pacific Ocean.  The high pressure system will steer Gilma toward the west during the next 24 hours.  On its anticipated track, Hurricane Gilma will move farther away from Baja California.