Tropical Storm Vance Forms South of Mexico

Tropical Storm Vance formed over the Eastern North Pacific Ocean south of Mexico on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Vance was located at latitude 9.4°N and longitude 99.8°W which put the center about 520 miles (835 km) south of Acapulco, Mexico.  Vance was moving toward the west at 7 m.p.h. (11 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 1003 mb.

A low pressure system over the Eastern North Pacific Ocean south of Mexico strengthened on Wednesday and the U.S. National Hurricane Center designated the system as Tropical Storm Vance.

More thunderstorms developed in bands revolving around the center of Tropical Storm Vance on Wednesday afternoon.  Storms near the center of Vance’s circulation began to generate upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the northern side of Tropical Storm Vance.  Winds to tropical storm force extended out 70 miles (110 km) in the northern side of Vance’s circulation.  The winds in the southern part of Tropical Storm Vance were blowing at less than tropical storm force.

Tropical Storm Vance will move through an environment favorable for intensification during the next 24 hours.  Vance will move over water where the Sea Surface Temperatures are near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Vance will intensify during the next 24 hours.  Vance could strengthen to a hurricane on Thursday.

Tropical Storm Vance will move around the southwestern part of a high pressure system that is over southern Mexico.  The high pressure system will steer Vance toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Vance will start to move closer to the west coast of Mexico on Thursday.

Subtropical Storm Josephine Develops Off East Coast

Subtropical Storm Josephine developed off the East Coast of the U.S. on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Subtropical Storm Josephine was located at latitude 37.4°N and longitude 69.5°W which put the center about 265 miles (425 km) south of Nantucket, Massachusetts.  Josephine was moving toward the north 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 990 mb.

The U.S. National Hurricane Center designated a low pressure system off the East Coast of the U.S. as Subtropical Storm Josephine on Wednesday afternoon.

Subtropical Storm Josephine made a transition from an extratropical cyclone to a subtropical cyclone on Wednesday.  The warm front and cold front that had been attached to the low pressure system dissipated.  Even though the fronts had dissipated, the distribution of thunderstorms in Subtropical Storm Josephine was asymmetrical.  Thunderstorms were occurring in bands in the northern and western parts of Josephine’s circulation.  Bands in the eastern and southern parts of Josephine consisted primarily of showers and lower clouds.

The distribution of wind speeds in Subtropical Storm Josephine was also asymmetrical.  Winds to tropical storm force extended out 415 miles (665 km) in the northern half of Josephine’s circulation.  Winds to tropical storm force extended out 150 miles (240 km) in the southern half of Subtropical Storm Josephine.

Subtropical Storm Josephine will move through an environment favorable for the intensification of a subtropical storm during the next 24 hours.  Josephine will move over water where the Sea Surface Temperatures are near 24°C.  It will move under the southeastern part of an upper level trough that will be over the Great Lakes.  The upper level trough will produce southwesterly winds that will blow toward the top of Josephine’s circulation.  Those winds will cause strong vertical wind shear.  However, the upper level winds may also contribute to upper level divergence.  Subtropical Storm Josephine could intensify on Thursday because of the upper level divergence.

The upper level trough over the Great Lakes will steer Subtropical Storm Josephine toward the northeast during the next 24 hours.  On its anticipated track, Subtropical Storm Josephine will pass south of Nova Scotia on Thursday.

Intense Typhoon Champi Churns West

Intense Typhoon Champi churned westward over the Western North Pacific Ocean on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Typhoon Champi was located at latitude 17.7°N and longitude 130.9°E which put the center about 670 miles (1080 km) south-southeast of Okinawa.  Champi was moving toward the west-northwest at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 185 m.p.h. (295 km/h) and there were wind gusts to 225 m.p.h. (360 km/h).  The minimum surface pressure was 895 mb.

Intense Typhoon Champi got even stronger on Tuesday.  A circular eye with a diameter of 35 miles (55 km) was at the center of Champi’s circulation.  Bands of showers and thunderstorms were revolving around the the center of Typhoon Champi.  Storms near the center of Champi generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The circulation around Typhoon Champi was large.  Winds to typhoon force extended out 100 miles (160 km) from the center of Champi’s circulation.  Winds to tropical storm force extended out 290 miles (465 km) from the center of Typhoon Champi.

The Hurricane Intensity Index (HII) for Typhoon Champi is 44.1.  The Hurricane Size Index (HSI) is 30.4 and the Hurricane Wind Intensity Size Index (HWISI) is 74.5.  Typhoon Champi is similar in intensity to Hurricane Dorian when Dorian hit the Bahamas in 2019.  Champi is much larger than Dorian was.

Typhoon Champi will move through an environment that will be favorable for an intense typhoon during the next 24 hours.  Champi 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.  Typhoon Champi could maintain its intensity during the next 24 hours unless the inner end of a rainband wraps around the existing eye and eyewall.  If concentric eyewalls form, then an eyewall replacement cycle would cause Champi to weaken.

Typhoon Champi will move around the southwestern part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Champi toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Champi will continue to move toward Taiwan and the southern Ryukyu Islands.  Champi could approach the southern Ryukyu Islands in 48 hours.

Tropical Cyclone Agueda Forms West of Seychelles

Tropical Cyclone Agueda formed over the South Indian Ocean west of the Seychelles on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Tropical Cyclone Agueda was located at latitude 5.2°S and longitude 52.5°E which put the center about 180 miles (290 km) west of the Seychelles.  Agueda 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.

A low pressure system over the South Indian Ocean west of the Seychelles strengthened on Tuesday and Meteo France la Reunion designated the system as Tropical Cyclone Agueda.

Thunderstorms were forming near the center of Tropical Cyclone Agueda.  Thunderstorms were also occurring in bands in the western side of Agueda’s circulation.  Bands in the eastern side of Tropical Cyclone Agueda consisted primarily of showers and lower clouds.  Storms near the center of Agueda generated upper level divergence that pumped mass away to the west of the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Agueda was small.  Winds to tropical storm force extended out 50 miles (80 km) from the center of Agueda’s circulation.

Tropical Cyclone Agueda will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Agueda will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the northern part of an upper level ridge that is over the South Indian Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Agueda’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear may not be enough to prevent intensification.  Tropical Cyclone Agueda could intensify during the next 24 hours.

Tropical Cyclone Agueda will move around the northern side of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Agueda toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Agueda will pass north of Madagascar later this week.

Typhoon Champi Strengthens to Equivalent of Cat. 5 Hurricane

Typhoon Champi strengthened to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale as it moved over the Western North Pacific Ocean north of Yap on Sunday night.  At 5:00 a.m. EDT on Monday the center of Typhoon Champi was located at latitude 14.6°N and longitude 137.9°E which put the center about 330 miles (535 km) north of Yap.  Champi was moving toward the west-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 105 m.p.h. (315 km/h).  The minimum surface pressure was 917 mb.

Typhoon Champi intensified to the equivalent of a Category 5 hurricane on Saturday night.  A circular eye with a diameter of 30 miles (50 km) was at the center of Champi’s circulation.  Bands of showers and thunderstorms were revolving around the the center of Typhoon Champi.  Storms near the center of Champi generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The size of the circulation around Typhoon Champi increased on Sunday.  Winds to typhoon force extended out 65 miles (105 km) from the center of Champi’s circulation.  Winds to tropical storm force extended out 220 miles (350 km) from the center of Typhoon Champi.

The Hurricane Intensity Index (HII) for Typhoon Champi is 35.0.  The Hurricane Size Index (HSI) is 20.8 and the Hurricane Wind Intensity Size Index (HWISI) is 55.8. Typhoon Champi is similar in size and intensity to Hurricane Maria when Maria hit Puerto Rico in 2017.

Typhoon Champi will move through an environment that will be favorable for intensification during the next 24 hours.  Champi 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.  Typhoon Champi could intensify during the next 24 hours unless the inner end of a rainband wraps around the existing eye and eyewall.  If concentric eyewalls form, then an eyewall replacement cycle would cause Champi to weaken.

Typhoon Champi will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Champi toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Champi will move toward Taiwan and the southern Ryukyu Islands.

Hurricane Trudy Rapidly Weakens

Hurricane Trudy weakened rapidly on Sunday evening as it moved over the Eastern North Pacific Ocean west of Mexico.  At 11:00 p.m. EDT on Sunday the center of Hurricane Trudy was located at latitude 19.7°N and longitude 107.6°W which put the center about 130 miles (215 km) west-southwest of Cabo Corrientes, Mexico.  Trudy was moving toward the northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (150 km/h).  The minimum surface pressure was 984 mb.

An upper level trough that was over Baja California was producing strong westerly winds that were blowing toward the top of Hurricane Trudy.  Those winds were causing strong vertical wind shear.  The strong vertical wind shear was causing Trudy to weaken rapidly on Sunday evening.  The strong upper level winds also blew the tops off of many of the thunderstorms in Hurricane Trudy.  There was much less upper level divergence that pumped less mass away from the hurricane.  The removal of mass in the upper levels was much less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure started to increase rapidly.

The size of the circulation around Hurricane Trudy was getting smaller on Sunday evening.  Winds to hurricane force extended our 25 miles (40 km) from the center of Trudy’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Hurricane Trudy.

Hurricane Trudy will move through an environment that will be unfavorable for intensification during the next 24 hours.  Trudy will move over water where the Sea Surface Temperatures are near 30°C.  However, the upper level trough over Baja California will continue to cause strong vertical wind shear.  The strong vertical wind shear will cause Hurricane Trudy to weaken to a tropical storm on Monday.

Since the strong vertical wind shear blew the tops off of many of the thunderstorms in Hurricane Trudy, Trudy will be steered by the winds lower in the atmosphere.  A high pressure system over northern Mexico will steer Trudy toward the west during the next 24 hours.  On its anticipated track, Hurricane Trudy will move farther away from Mexico on Monday.

Typhoon Champi Brings Wind and Rain to Guam

Typhoon Champi brought wind and rain to Guam on Saturday.  At 5:00 p.m. EDT on Saturday the center of Typhoon Champi was located at latitude 13.2°N and longitude 144.3°E which put the center about 40 miles (65 km) south of Guam.  Champi was moving toward the west-northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h).  The minimum surface pressure was 934 mb.

Typhoon Warnings are in effect for Guam and Rota,

Tropical Storm Warnings are in effect for Tinian and Saipan.

The core of Typhoon Champi where the strongest winds are occurring passed just to the south of Guam on Saturday.  Bands in the northern side of Champi’s circulation brought strong winds and rain to Guam, Rota, Tinian and Saipan.

A weather station at the Guam International Airport (PGUM) reported a sustained wind speed of 47 m.p.h. (76 km/h) and a wind gust of 72 m.p.h. (116 km/h).

A weather station at Andersen Air Force Base (PGUA) reported a sustained wind speed 0f 46 m.p.h. (74 km/h) and a wind gust of 59 m.p.h. (95 km/h).

Typhoon Champi was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.  Winds to typhoon force extended out 60 miles (95 km) from the center of Champi’s circulation.  Winds to tropical storm force extended out 140 miles (225 km) from the center of Typhoon Champi.

The Hurricane Intensity Index (HII) for Typhoon Champi is 31.6.  The Hurricane Size Index (HSI) is 18.6 and the Hurricane Wind Intensity Size Index (HWISI) is 50.2.  Typhoon Champi is similar in size and intensity to Hurricane Laura when Laura hit Southwest Louisiana in 2020.

Typhoon Champi will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Champi toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Champi will move away from Guam on Sunday.

Typhoon Champi will move through an environment that will be favorable for intensification during the next 24 hours.  Champi 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 that is over the Western North Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Champi’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.  Typhoon Champi could intensify during the next 24 hours unless the inner end of a rainband wraps around the existing eye and eyewall.  If concentric eyewalls form and an eyewall replacement cycle occurs, Champi will weaken, at least temporarily.

Hurricane Trudy Moves Closer to Mexico

Hurricane Trudy moved closer to the west coast of Mexico on Saturday.  At 5:00 p.m. EDT on Saturday the center of Hurricane Trudy was located at latitude 17.5°N and longitude 105.0°W which put the center about 115 miles (185 km) south-southwest of Manzanillo, Mexico.  Trudy was moving toward the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 976 mb.

A Hurricane Warning is in effect for the portion of the coast from Manzanillo to Cabo Corrientes, Mexico.

A Hurricane Watch is in effect for the portion of the coast from Manzanillo to Punta San Telmo, Mexico.

A Tropical Storm Warning is in effect for the portion of the coast from Manzanillo to Lazaro Cardenas, Mexico.

A Tropical Storm Warning is in effect for the portion of the coast from Cabo Corrientes to San Blas, Mexico.

A Tropical Storm Warning is in effect for Las Islas Marias.

Hurricane Trudy appeared to go through an eyewall replacement cycle during the past 24 hours.

A circular eye with a diameter of 45 miles (75 km) was at the center of Trudy’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 Trudy’s circulation.  Storms near the core of Trudy generated upper level divergence that pumped mass away from the hurricane.  The removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So the surface pressure increased on Saturday.

The distribution of wind speeds in Hurricane Trudy was fairly symmetrical.  Winds to hurricane force extended out 35 miles (55 km) from the center of Trudy’s circulation.  Winds to tropical storm force extended out 140 miles (225 km) from the center of Hurricane Trudy.

The Hurricane Intensity Index (HII) for Hurricane Trudy is 16.5.  The Hurricane Size Index (HSI) is 12.6 and the Hurricane Wind Intensity Size Index (HWISI) is 29.1.  Hurricane Trudy is similar in intensity to Hurricane Idalia when Idalia hit Florida in 2023.  Trudy is larger than Isaias was.

Hurricane Trudy will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Trudy will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the southeastern part of an upper level trough that is near Baja California.  The upper level trough will produce westerly winds that will blow toward the top of Trudy’s circulation.  Those winds will cause the vertical wind shear to increase.  Hurricane Trudy could intensify on Sunday if the vertical wind shear does not increase too much.

Hurricane Trudy will move around the western side of a high pressure system that is over Mexico.  The high pressure system will steer Trudy toward the northwest during the next 24 hours.  On its anticipated track, the center of Hurricane Trudy will approach the west coast of Mexico between Manzanillo and Cabo Corrientes.

The center of Hurricane Trudy is forecast to remain west of Mexico.  However, bands in the eastern side of Trudy’s circulation will bring strong winds and heavy rain to the west coast of Mexico between Manzanillo and Cabo Corrientes.  Heavy rain is likely to cause flash floods in some locations.

Tropical Cyclone Wati Forms over South Pacific

Tropical Cyclone Wati formed over the South Pacific Ocean east of Samoa on Friday night.  At 5:00 a.m. EDT on Saturday the center of Tropical Cyclone Wati was located at latitude 13.6°S and longitude 163.1°W which put the center about 510 miles (820 km) east of Pago Pago, Samoa.  Wati was moving toward the south-southeast at 14 m.p.h. (22 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 986 mb.

A low pressure system over the South Pacific Ocean east of Samoa strengthened on Saturday night and the Fiji Meteorological Service designated the system as Tropical Cyclone Wati.

Thunderstorms were occurring near the center of Tropical Cyclone Wati.  Bands of showers and thunderstorms were revolving around the center of Wati’s circulation.  Storms near the center of Wati generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

Winds to tropical storm force extended out 100 miles (160 km) from the center of Tropical Cyclone Wati.

Tropical Cyclone Wati will move through an environment that will be favorable for intensification during the next 24 hours.  Wati will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the western part of an upper level ridge that is over the South Pacific Ocean.  The upper level ridge will produce northerly winds that will blow toward the top of Wati’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but wind shear will not be enough to prevent intensification.  Tropical Cyclone Wati will intensify during the next 24 hours.  Wati is likely to strengthen to the equivalent of a hurricane/typhoon.

Tropical Cyclone Wati will move around the western end of a high pressure system that is over the South Pacific Ocean.  The high pressure system will steer Wati toward the south-southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Wati will move farther away form Samoa.  Wati will move over Aitutaki on Sunday.

Tropical Cyclone Wati will bring strong winds and heavy rain to Aitutaki.  Heavy rain is likely to cause flash floods.

 

Typhoon Champi Rapidly Intensified to Equivalent of Major Hurricane

Typhoon Champi rapidly intensified to the equivalent of a major hurricane as it moved closer to Guam on Friday night.  At 5:00 a.m. EDT on Saturday the center of Typhoon Champi was located at latitude 12.6°N and longitude 146.7°E which put the center about 180 miles (295 km) east-southeast of Guam.  Champi was moving toward the west at 15 m.p.h. (24 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 948 mb.

Typhoon Warnings are in effect for Guam and Rota,

Tropical Storm Warnings are in effect for Tinian and Saipan.

Typhoon Champi rapidly intensified to the equivalent of a major hurricane on Friday night.  A small circular eye with a diameter of 6 miles (10 km) was at the center of Champi’s circulation. Bands of showers and thunderstorms were revolving around the the center of Typhoon Champi.  Storms near the center of Champi generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speed became more symmetrical when Typhoon Champi rapidly intensified.  Winds to typhoon force extended out 60 miles (95 km) from the center of Champi’s circulation.  Winds to tropical storm force extended out 130 miles (210 km) from the center of Typhoon Champi.

The Hurricane Intensity Index (HII) for Typhoon Champi is 25.1.  The Hurricane Size Index (HSI) is 18.5 and the Hurricane Wind Intensity Size Index (HWISI) is 43.6.  Typhoon Champi is similar in intensity to Hurricane Harvey when Harvey hit Texas in 2017.  Champi is bigger than Harvey was.

Typhoon Champi will move through an environment that will be favorable for intensification during the next 24 hours.  Champi 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 that is over the Western North Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Champi’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.  Typhoon Champi will intensify during the next 24 hours.  Champi could strengthen to the equivalent of a Category 5 hurricane on Saturday.

Typhoon Champi will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Champi toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Champi will reach Guam in less than 12 hours.

Typhoon Champi is could be the equivalent of a Category 5 hurricane when it reaches Guam.  Champi will bring strong winds and heavy rain to Guam, Rota, Tinian and Saipan.  The strongest winds and heaviest rain are likely to affect Guam and Rota.  Typhoon Champi will be capable of causing severe damage in Guam.  Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for Guam, Rota, Tinian and Saipan.