Category Archives: Tropical Cyclones

Information about tropical cyclones

Priscilla and Octave Intensify to Hurricanes

Former Tropical Storms Priscilla and Octave both intensified to hurricanes over the Eastern North Pacific Ocean on Sunday.  At 8:00 p.m. EDT on Sunday the center of Hurricane Priscilla was located at latitude 16.5°N and longitude 107.1°W which put the center about 285 miles (460 km) south-southwest of Cabo Corrientes, Mexico.  Priscilla was moving toward the north-northwest at 3 m.p.h. (5 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 986 mb.

A Tropical Storm Watch was issued for the portion of the coast from Punta San Telmo to Punta Mita, Mexico.

Former Tropical Storm Priscilla intensified to a hurricane southwest of Mexico on Sunday.  The inner end of a rainband wrapped around the southern side of the center of Priscilla’s circulation.  An eye appeared to be forming at the center of Hurricane Priscilla.  Other bands of showers and thunderstorms were revolving around the center of Priscilla’s circulation.  Storms near the center of Priscilla generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the southeastern part of Hurricane Priscilla.  Hurricane force winds extended out 40 miles in the southeastern quadrant of Priscilla’s circulation.  Winds to tropical storm force extended out 175 miles (280 km) from the center of Hurricane Priscilla.

Hurricane Priscilla will move through an environment favorable for intensification during the next 24 hours.  Priscilla will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the middle of an upper level ridge over Mexico and the Eastern North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Hurricane Priscilla will intensify during the next 24 hours.  Priscilla could strengthen to a major hurricane by Tuesday.

Hurricane Priscilla will move around the western end of a high pressure system over Mexico.  The high pressure system will steer Priscilla slowly toward the north-northwest during the next 24 hours.  On its anticipated track, Hurricane Priscilla will move south of Baja California on Tuesday.

Elsewhere over the Eastern North Pacific Ocean, former Tropical Storm Octave also intensified to a hurricane on Sunday.  At 5:00 p.m. EDT on Sunday the center of Hurricane Octave was located at latitude 16.0°N and longitude 123.3°W which put the center about 995 miles (1600 km) south-southwest of the southern tip of Baja California.  Octave was moving toward the northeast at 6 m.p.h. (10 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 987 mb.

Typhoon Matmo Brings Wind and Rain to Southern China

Typhoon Matmo brought wind and rain to southern China on Sunday morning.  At 5:00 a.m. EDT on Sunday the center of Typhoon Matmo was located at latitude 21.1°N and longitude 110.0°E which put the center about 25 miles (40 km) west of Zhanjiang, China.  Matmo was moving toward the west-northwest at 14 m.p.h. (25 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 966 mb.

Typhoon Matmo strengthened to the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale before it made landfall on the coast of southern China on Sunday morning.  The center of Matmo made landfall near Zhanjiang.

Typhoon Matmo was a large typhoon at the time of landfall.  Winds to typhoon force extended out 70 miles (110 km) from the center of Matmo’s circulation.  Winds to tropical storm force extended out 175 miles (280 km) from the center of Typhoon Matmo.

The Hurricane Intensity Index (HII) for Typhoon Matmo was 17.8.  The Hurricane Size Index (HSI) was 23.2 and the Hurricane Wind Intensity Size index (HWISI) was 41.0.  Typhoon Matmo was similar in size and intensity to Hurricane Gustav when Gustav hit Louisiana in 2008.

Typhoon Matmo will move around the southern side of a high pressure system that is over southern China.  The high pressure system will steer Matmo toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Matmo will move inland near the coast of southern China.

Typhoon Matmo will bring strong winds and heavy rain to southwestern Guangdong, Guangxi, and Hainan.  Heavy rain is likely to cause floods in some locations.  Matmo could also cause a storm surge of up to 10 feet (3 meters) along parts of the coast.  Typhoon Matmo will drop heavy rain on parts of northern Vietnam early next week.

Elsewhere over the Western North Pacific Ocean, former Tropical Depression 28W strengthened to Tropical Storm Halong east of Iwo To.  At 5:00 a.m. EDT on Sunday the center of Tropical Storm Halong was located at latitude 25.0°N and longitude 142.0°E which put the center about 65 miles (105 km) east of Iwo To.   Halong was moving toward the west-northwest at 5 m.p.h. (8 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 994 mb.

Tropical Storm Priscilla Forms Southwest of Mexico

Tropical Storm Priscilla formed over the Eastern North Pacific Ocean southwest of Mexico on Saturday afternoon.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Priscilla was located at latitude 15.5°N and longitude 106.6°W which put the center about 285 miles (460 km) south-southwest of Manzanillo, Mexico.  Priscilla was moving toward the northwest 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 1002 mb.

A Tropical Storm Watch was issued for the portion of the coast from Punta San Telmo to Punta Mita, Mexico.

A low pressure system over the Eastern North Pacific Ocean southwest of Mexico strengthened on Saturday afternoon and the U.S. National Hurricane Center designated the system as Tropical Storm Priscilla.

The circulation around Tropical Storm Priscilla was large.  More thunderstorms formed near the center of Priscilla’s circulation on Saturday afternoon.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Priscilla.  Storms near the center of Priscilla began to generate upper level divergence that pumped mass away from the tropical storm.

The strongest winds were occurring in the northern side of Tropical Storm Priscilla.  Winds to tropical storm force extended out 140 miles (225 km) in the northern part of Priscilla’s circulation.  The winds in the southern side of Tropical Storm Priscilla were blowing at less than tropical storm force.

Tropical Storm Priscilla will move through an environment favorable for intensification during the next 24 hours.  Priscilla will move over water where the Sea Surface Temperatures are near 28°C.   It will move under the middle of an upper level ridge over Mexico and the Eastern North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Storm Priscilla will intensify during the next 24 hours.  Priscilla could strengthen to a hurricane by Monday.

Tropical Storm Priscilla will move around the western end of a high pressure system over Mexico.  The high pressure system will steer Priscilla slowly toward the north-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Priscilla will move a little closer toward the west coast of Mexico.

Elsewhere over the Eastern North Pacific Ocean, Tropical Storm Octave continued to meander far to the south-southwest of Baja California.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Octave was located at latitude 14.9°N and longitude 123.9°W which put the center about 1065 miles (1720 km) south-southwest of the southern tip of Baja California.  Octave was moving toward the north-northwest 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 997 mb.

Tropical Cyclone Shakhti Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Shakhti intensified to the equivalent of a hurricane/typhoon over the Arabian Sea south of Pakistan on Saturday.  At 11:00 a.m. EDT on Saturday the center of Tropical Cyclone Shakhti was located at latitude 21.2°N and longitude 63.1°E which put the center about 330 miles (535 km) southwest of Karachi, Pakistan.  Shakhti was moving toward the west-southwest at 9 m.p.h. (15 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 982 mb.

Tropical Cyclone Shankhti intensified to the equivalent of a hurricane/typhoon over the Arabian Sea south of Pakistan on Saturday.  The inner end of a rainband wrapped around the center of Shakhti’s circulation.  A small eye was visible at the center of Tropical Cyclone Shakhti.  The eye was surrounded by a thin ring of thunderstorms and the strongest winds were in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Shakhti’s circulation.  Storms near the center of Shakhti generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the southern part of Tropical Cyclone Shakhti.  Winds to hurricane/typhoon force extended out 30 miles (50 km) on the southern side of Shakhti’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Tropical Cyclone Shakhti.

Tropical Cyclone Shakhti will move through an environment somewhat favorable for intensification during the next 24 hours.  Shakhti 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 Pakistan and the northern Arabian Sea.  The upper level ridge will produce easterly winds that will blow toward the top of Shakhti’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  However, drier air over southern Asia could get pulled into the northern side of Tropical Cyclone Shakhti.  The drier air will also inhibit intensification.  Tropical Cyclone Shakhti could intensify during the next 24 hours if the drier air stays around the northern periphery of its circulation.

Tropical Cyclone Shakhti will move around the southern side of a high pressure system over Pakistan.  The high pressure system will steer Shakhti toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Shakhti will stay south of Pakistan during the weekend.

 

Typhoon Matmo Passes South of Hong Kong

Typhoon Matmo passed south of Hong Kong on Saturday.  At 11:00 a.m. EDT on Saturday the center of Typhoon Matmo was located at latitude 19.3°N and longitude 113.4°E which put the center about 225 miles (370 km) south of Hong Kong, Philippines.  Matmo was moving toward the west-northwest at 16 m.p.h. (26 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 984 mb.

Typhoon Matmo strengthened as it passed south of Hong Kong on Saturday.  The inner end of a rainband wrapped around the center of Matmo’s circulation.  A circular eye formed at the center of Typhoon Matmo.  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 Matmo’s circulation.  Storms near the core of Matmo 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 Matmo increased on Saturday.  Winds to typhoon force extended out 35 miles (55 km) from the center of Matmo’s circulation.  Winds to tropical storm force extended out 175 miles (280 km) from the center of Typhoon Matmo.

Typhoon Matmo will move through an environment favorable for intensification during the next 12 hours.  Matmo will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge that is over China.  The upper level ridge will produce easterly winds that will blow toward the top of Matmo’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Typhoon Matmo will intensify during the next 12 hours. .

Typhoon Matmo will move around the southern side of a high pressure system that is over southern China.  The high pressure system will steer Matmo toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Matmo will approach the  southern coast of China in 12 hours.

Typhoon Matmo will bring strong winds and heavy rain to southwestern Guangdong, Guangxi, and Hainan.  Heavy rain is likely to cause floods in some locations.  Matmo also cause a storm surge of up to 10 feet (3 meters) along portions of the coast.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 28W formed east of Iwo To.  At 11:00 a.m. EDT on Saturday the center of Tropical Depression 28W was located at latitude 21.2°N and longitude 63.1°E which put the center about 125 miles (200 km) east of Iwo To.  The tropical depression was moving toward the north at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 55 m.p.h. (90 km/h).  The minimum surface pressure was 1003 mb.

Tropical Storm Matmo Moves over South China Sea

Tropical Storm Matmo moved over the South China Sea on Friday morning after crossing northern Luzon.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Matmo was located at latitude 17.7°N and longitude 118.7°E which put the center about 120 miles (195 km) west of Vigan, Philippines.  Matmo 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.

Former Typhoon Matmo weakened back to a tropical storm after it moved across northern Luzon.  A circular eye was still visible at the center of Matmo’s circulation on satellite images.  The eye was surrounded by a broken 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 Matmo’s circulation.  Storms near the center of Matmo generated upper level divergence that pumped mass away from the tropical storm.

The circulation around Tropical Storm Matmo was symmetrical.  Winds to tropical storm force extended out 120 miles (195 km) from the center of Matmo’s circulation.

Tropical Storm Matmo will move through an environment favorable for intensification during the next 24 hours.  Matmo will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge that is over China.  The upper level ridge will produce easterly winds that will blow toward the top of Matmo’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Storm Matmo will intensify during the next 24hours.  Matmo is likely to strengthen back to a typhoon later today.

Tropical Storm Matmo will move around the southern side of a high pressure system that is over southern China.  The high pressure system will steer Matmo toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Matmo will pass south of Hong Kong in 24 hours. Matmo will be near Hainan in 36 hours.

Tropical Cyclone Shakhti Forms over Arabian Sea

Tropical Cyclone Shakhti formed over the northern Arabian Sea south of Pakistan on Friday morning.  At 5:00 a.m. EDT on Friday the center of Tropical Cyclone Shakhti was located at latitude 21.9°N and longitude 66.6°E which put the center about 205 miles (335 km) south of Karachi, Pakistan.  Shakhti was moving toward the northwest at 6 m.p.h. (10 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 993 mb.

A low pressure system over the northern Arabian Sea strengthened on Friday morning and the India Meteorological Department designated the system as Tropical Cyclone Shakhti.

The circulation around Tropical Cyclone Shakhti was gradually becoming more organized.  Thunderstorms developed near the center of Shakhti’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Shakhti.  Storms near the center of Shakhti began to generate upper level divergence that pumped mass away from the tropical cyclone.

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

Tropical Cyclone Shakhti will move through an environment favorable for intensification during the next 24 hours.  Shakhti will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the middle of an upper level ridge that is over Pakistan and the northern Arabian Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Shakhti will intensify during the next 24 hours.

Tropical Cyclone Shakhti will move around the southern side of a high pressure system over Pakistan.  The high pressure system will steer Shakhti toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Shakhti will move parallel to the coast of Pakistan.

 

Typhoon Matmo Brings Wind and Rain to Luzon

Typhoon Matmo brought strong winds and rain to Luzon on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Typhoon Matmo was located at latitude 16.6°N and longitude 119.6°E which put the center about 25 miles (40 km) southeast of Canayan, Philippines.  Matmo was moving toward the west-northwest 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 989 mb.

Former Tropical Storm Matmo strengthened to a typhoon as it approached Luzon on Thursday.  The inner end of a rainband wrapped most of the way around the center of Matmo’s circulation.  An eye started to form at the center of Typhoon Matmo before if made landfall in Luzon.  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 Matmo’s circulation.  Storms near the center of Matmo 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 Matmo was small.  Winds to typhoon force extended out 20 miles (30 km) from the center of Matmo’s circulation.  Winds to tropical storm force extended out 120 miles (195 km) from the center of Typhoon Matmo.

Typhoon Matmo will weaken slightly while it moves across northern Luzon during the next few hours.  Matmo will move into an environment favorable for intensification when it moves over the South China Sea on Friday.  Matmo will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over the Western North Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Matmo’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification. Typhoon Matmo will start to intensify again when it moves over the South China Sea.

Typhoon Matmo will move around the southern side of a high pressure system that is south of Japan.  The high pressure system will steer Matmo toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Matmo will move across northern Luzon during the next few hours.  Matmo will move over the South China Sea on Friday.

Typhoon Matmo will cause strong winds and heavy rain in northern Luzon.  The strong winds could cause electricity outages.  Heavy rain is likely to cause flash floods in some location. Typhoon Matmo could also cause a storm surge of up to 7 feet (2 meters).

Hurricane Imelda Brings Wind and Rain to Bermuda

Hurricane Imelda brought wind and rain to Bermuda on Wednesday night.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Imelda was located at latitude 32.1°N and longitude 65.0°W which put the center about 20 miles (30 km) southwest of Bermuda.  Imelda was moving toward the east-northeast at 29 m.p.h. (46 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 971 mb.

A Hurricane Warning is in effect for Bermuda.

Hurricane Imelda was in the middle of a transition to an extratropical cyclone when it reached Bermuda on Wednesday night.  The transition to an extratropical cyclone affected the structure of Hurricane Imelda.  Thunderstorms were occurring in bands in the northern side of Imelda’s circulation.  The bands in the southern half of Hurricane Imelda consisted primarily of showers and lower clouds.

The size of the circulation around Hurricane Imelda increased during the transition to an extratropical cyclone.  Winds to hurricane force extended out 45 miles (75 km) from the center of Imelda’s circulation.  Winds to tropical storm force extended out 250 miles (400 km) from the center of Hurricane Imelda.

The Hurricane Intensity Index (HII) for Hurricane Imelda was 16.5. The Hurricane Size Index (HSI) was 15.6 and the Hurricane Wind Intensity Size Index (HWISI) was 32.1.

Hurricane Imelda will continue to bring strong winds and heavy rain to Bermuda during the next few hours. The strong winds could cause electricity outages.  Heavy rain could cause flooding.

Hurricane Imelda will move through an environment unfavorable for intensification of a hurricane during the next 24 hours.  Imelda will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southern side of an upper level trough that is east of the U.S.  The upper level trough will produce strong southwesterly winds that will blow toward the top of Imelda’s circulation.  Those winds will cause strong vertical wind shear.  The strong vertical wind shear will cause Hurricane Imelda to complete a transition to a strong extratropical cyclone on Thursday.

The upper level trough east of the U.S. will steer Hurricane Imelda toward the east-northeast during the next 24 hours.  On its anticipated track, Hurricane Imelda will move quickly away from Bermuda on Thursday.

Tropical Storm Octave Spins South of Baja California

Tropical Storm Octave was spinning over the Eastern North Pacific Ocean far to the south of Baja California on Wednesday evening.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Octave was located at latitude 12.2°N and longitude 117.0°W which put the center about 875 miles (1405 km) south-southwest of the southern tip of Baja California.  Octave was moving toward the west-northwest at 7 m.p.h. (11 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 994 mb.

Tropical Storm Octave strengthened on Wednesday.  The inner end of a rainband wrapped around the southern and eastern sides of the center of Octave’s circulation.  Bands of thunderstorms were in the western half of Tropical Storm Octave.  The bands in the eastern part of Octave’s circulation still consisted primarily of showers and lower clouds.  The storms near the center of Octave generated upper level divergence that pumped mass away to the west of the tropical storm.  The removal of mass caused the surface pressure to decrease.

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

Tropical Storm Octave will move through an environment somewhat favorable for intensification during the next 24 hours.  Octave will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southern side of an upper level ridge that is over the Eastern North Pacific Ocean.  The upper level ridge will produce northeasterly winds that will blow toward the top of Octave’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 Storm Octave could intensify gradually during the next 24 hours.

Tropical Storm Octave will move around the western end of a high pressure system over Mexico and the Eastern North Pacific Ocean.  The high pressure system will steer Octave toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Octave will remain far to the south of Baja California.