Category Archives: Tropical Cyclones

Information about tropical cyclones

Typhoon Danas Hits Taiwan

Typhoon Danas hit Taiwan on Sunday.  At 11:00 a.m. EDT on Sunday the center of Typhoon Danas was located at latitude 23.5°N and longitude 120.0°E which put the center about 75 miles (120 km) southwest of Taichung, Taiwan.  Danas was moving toward the northeast at 13 m.p.h. (21 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 958 mb.

Typhoon Danas rapidly intensified to the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale as it approached Taiwan on Sunday.  The inner end of a rainband wrapped around the center of Danas’ circulation.  A circular eye with a diameter of 16 miles (26 km) formed at the center of Typhoon Danas.  Other bands of showers and thunderstorms were revolving around the core of Danas’ circulation.

The size of the circulation around Typhoon Danas increased when Danas rapidly intensified.  Winds to typhoon force extended out 35 miles (55 km) from the center of Danas’ circulation.  Winds to tropical storm force extended out 160 miles (260 km) in the eastern side of Typhoon Danas.  Winds to tropical storm force extended out 85 miles (135 km) in the western side of Danas.

The Hurricane Intensity Index (HII) for Typhoon Danas is 17.8.  The Hurricane Size Index (HSI) is 14.4 and the Hurricane Wind Intensity Size Index (HWISI) is 32.2.  Typhoon Danas is similar in size and intensity to Hurricane Sally when Sally hit Alabama in 2020.

Typhoon Danas will bring strong, gusty winds and heavy rain to Taiwan.  Heavy rain is likely to cause flash floods and mudslides.  Widespread outages of electricity are possible.  Typhoon Danas could also cause a storm surge of up to 10 feet (3 meters) along parts of the coast of Taiwan.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Mun continued to churn east of Japan.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Mun was located at latitude 33.9°N and longitude 149.4°E which put the center about 545 miles (875 km) east of Tokyo, Japan.  Mun was moving toward the north at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 982 mb.

Tropical Storm Chantal Brings Wind and Rain to the Carolinas

Tropical Storm Chantal brought wind and rain to the Carolinas on Sunday morning.  At 5:00 a.m. EDT on Sunday the center of Tropical Storm Chantal was located at latitude 33.6°N and longitude 79.1°W which put the center about 5 miles (10 km) west of Myrtle Beach, South Carolina.   Chantal was moving toward the north-northwest at 8 m.p.h. (13 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 1004 mb.

A Tropical Storm Warning is in effect for the portion of the coast from South Santee River, South Carolina to Surf City, North Carolina.

The center of Tropical Storm Chantal made landfall on the coast of South Carolina just to the west of Myrtle Beach early on Sunday.  The distribution of wind and rain in Chantal was asymmetrical.  Heavier rain was occurring in bands in the eastern side of Chantal’s circulation.  Bands in the western part of Tropical Storm Chantal consisted primarily of showers and lower clouds.

The distribution of wind speeds in Tropical Storm Chantal was also asymmetrical.  The strongest winds were occurring in bands of thunderstorms in the northeastern part of Chantal’s circulation.  Winds to tropical storm force extended out 115 miles (185 km) in the eastern side of Tropical Storm Chantal.  Winds to tropical storm force extended out 35 miles (55 km) in the western side of Chantal.

Tropical Storm Chantal will move around the western side of a high pressure system over the Atlantic Ocean.  The high pressure system will steer Chantal toward the north during the next 24 hours.  On its anticipated track, Tropical Storm Chantal will move inland over eastern North Carolina.

Tropical Storm Chantal will bring strong winds and locally heavy rain to eastern South Carolina and to eastern North Carolina.  Chantal will weaken gradually as it moves farther inland.  The heaviest rain and strongest winds will occur in the northeastern part of Chantal’s circulation.  Heavy rain could cause flash floods in some locations.  Tropical Storm Chantal could cause a storm surge of up to four feet (one meter).  Chantal will also bring high waves to the coast. The waves could cause beach erosion.

Flood Watches are in effect for portions of eastern South Carolina and Eastern North Carolina.

Tropical Storm Chantal Strengthens a Little

Tropical Storm Chantal strengthened a little as it approached the Carolinas on Saturday evening.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Chantal was located at latitude 32.7°N and longitude 78.8°W which put the center about 65 miles (105 km) east of Charleston, South Carolina.  Chantal was moving toward the north at 8 m.p.h. (13 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 1004 mb.

A Tropical Storm Warning is in effect for the portion of the coast from South Santee River, South Carolina to Surf City, North Carolina.

A Tropical Storm Watch is in effect for the portion of the coast from Edisto Beach to South Santee River, South Carolina.

Tropical Storm Chantal strengthened a little as it approached the Carolinas on Saturday evening.  Even though Chantal was a little stronger, the distribution of thunderstorms was still asymmetrical.  Thunderstorms were occurring in bands in the eastern side of Chantal’s circulation.  Bands in the western part of Tropical Storm Chantal consisted primarily of showers and lower clouds.  Storms east of the center of Chantal’s circulation generated upper level divergence that pumped mass away to the north and east of the tropical storm.  The removal of mass caused the surface pressure to decrease slowly.

The distribution of wind speeds in Tropical Storm Chantal was also asymmetrical. The strongest winds were occurring in bands of thunderstorms in the northeastern part of Chantal’s circulation.  Winds to tropical storm force extended out 140 miles (220 km) in the eastern side of Tropical Storm Chantal.  Winds to tropical storm force extended out 35 miles (55 km) in the western side of Chantal.

Tropical Storm Chantal will move through an environment that will be somewhat favorable for intensification during the next few hours.  Chantal will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the northeastern part of an upper level low over the southeastern U.S.  The upper level low will produce southwesterly winds that will blow toward the top of Chantal’s circulation.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but the shear may not be enough to prevent intensification.  Tropical Storm Chantal could intensify a little more during the next few hours.

The upper level low over the southeastern U.S. will steer Tropical Storm Chantal toward the north during the next 24 hours.  On its anticipated track, Tropical Storm Chantal will make landfall on the coast near the border between South Carolina and North Carolina in a few hours.

Tropical Storm Chantal will bring strong winds and locally heavy rain to eastern South Carolina and to eastern North Carolina.  The heaviest rain and strongest winds will occur in the northeastern part of Chantal’s circulation.  Heavy rain could cause flash floods in some locations.  Tropical Storm Chantal could cause a storm surge of up to four feet (one meter).  Chantal will also bring high waves to the coast. The waves could cause beach erosion.

Flood Watches are in effect for portions of eastern South Carolina and Eastern North Carolina.

Danas Intensifies to a Typhoon Southwest of Taiwan

Former Tropical Storm Danas intensified to a typhoon over the South China Sea southwest of Taiwan on Saturday.  At 5:00 p.m. EDT on Saturday the center of Typhoon Danas was located at latitude 21.4°N and longitude 118.3°E which put the center about 170 miles (275 km) southwest of Kaohsiung, Taiwan.  Danas was moving toward the north-northeast at 4 m.p.h. (6 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 977 mb.

Former Tropical Storm Dana intensified to a typhoon over the South China Sea southwest of Taiwan on Saturday.  The distribution of thunderstorms in Typhoon Danas became more symmetrical as Danas intensified.  More thunderstorms developed near the center of Danas’ circulation.  More thunderstorms also formed in bands revolving around the center of Typhoon Danas.  Storms near the center of Danas 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 Danas increased as Danas intensified.  Winds to typhoon force extended out 35 miles (55 km) from the center of Danas’ circulation.  Winds to tropical storm force extended out 140 miles (220 km) from the center of Typhoon Danas.

Typhoon Danas will move through an environment mostly favorable for intensification during the next 18 hours.  Danas will move over water where where the Sea Surface Temperatures are near 29°C.  It will move under the western part of an upper level ridge over that is centered east of Taiwan.  The upper level ridge will produce southwesterly winds that will blow toward the top of Danas’ 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. Typhoon Danas will intensify during the next 18 hours.  Danas could intensify rapidly at times.

Typhoon Danas will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Danas toward the north-northeast during the next 24 hours.  On its anticipated track, Typhoon Danas will approach the west coast of Taiwan in 18 hours.

Typhoon Danas will bring strong winds and locally heavy rain to Taiwan. Heavy rain is likely to cause flash floods. Typhoon Danas could also cause a storm surge of up to 10 feet (3 meters) along parts of the coast of Taiwan.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Mun continued to churn east-southeast of Japan.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Mun was located at latitude 32.0°N and longitude 148.9°E which put the center about 575 miles (925 km) east-southeast of Tokyo, Japan.  Mun was moving toward the northeast at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 983 mb.

Depression Strengthens to Tropical Storm Chantal

Former Tropical Depression Three strengthened to Tropical Storm Chantal on Sunday morning.  At 8:00 a.m. EDT on Saturday the center of Tropical Storm Chantal was located at latitude 30.9°N and longitude 79.0°W which put the center about 150 miles (240 km) south-southeast of Charleston, South Carolina.  Chantal was moving toward the north at 2 m.p.h. (3 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 1009 mb.

A Tropical Storm is in effect for the portion of the coast from South Santee River, South Carolina to Cape Fear, North Carolina.

A Tropical Storm Watch is in effect for the portion of the coast from Edisto Beach to South Santee River, South Carolina.

Former Tropical Depression Three strengthened to Tropical Storm Chantal on Sunday morning.  Even though it strengthened, the distribution of thunderstorms in Tropical Storm Chantal was asymmetrical.  Thunderstorms were occurring in bands in the eastern side of Chantal’s circulation.  Bands in the western part of Tropical Storm Chantal consisted primarily of showers and lower clouds.  Storms east of the center of Chantal’s circulation generated upper level divergence that pumped mass away to the north and east of the tropical storm.

The distribution of wind speeds in Tropical Storm Chantal was also asymmetrical.  Winds to tropical storm force extended out 70 miles (110 km) in the eastern side of Chantal’s circulation.  The winds in the western side of Tropical Storm Chantal were blowing at less than tropical storm force.

Tropical Storm Chantal will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Chantal will move over water where where the Sea Surface Temperatures are near 29°C.  It will move under the eastern side of an upper level trough over the southeastern U.S.  The upper level trough will produce southwesterly winds that will blow toward the top of Chantal’s circulation.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Storm Chantal is likely to intensify during the next 24 hours.

The upper level trough over the Southeastern U.S. will steer Tropical Storm Chantal toward the north during the next 24 hours.  On its anticipated track, Tropical Storm Chantal will move toward the coast of South Carolina.  Chantal is likely to make landfall on Sunday.

Tropical Storm Chantal will bring strong winds and locally heavy rain to South Carolina and North Carolina.  Heavy rain could cause flash floods in some locations.  Chantal will also bring high waves to the coast.  The waves could cause beach erosion.

Tropical Depression Three Forms Off Southeast U.S.

Tropical Depression Three formed off the coast of the Southeast U.S. on Friday afternoon.  At 5:00 p.m. EDT on Friday the center of Tropical Depression Three was located at latitude 30.8°N and longitude 79.0°W which put the center about 150 miles (240 km) south-southeast of Charleston, South Carolina.  The tropical depression was moving toward the north at 2 m.p.h. (3 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 1012 mb.

A Tropical Storm Watch is in effect for the portion of the coast from Edisto Beach to Little River Inlet, South Carolina.

A low pressure system over the Atlantic Ocean off the Southeast U.S. coast strengthened on Friday afternoon.  Based on satellite images and data collected by a U.S. Air Force Reserve Hurricane Hunter aircraft, the U.S. National Hurricane Center designated the system as Tropical Depression Three.

More thunderstorms formed near the center of Tropical Depression Three.  Thunderstorms also developed in bands in the northern and eastern parts of the tropical depression.  Storms near the center of circulation began to generate upper level divergence that pumped mass away to the north and east of the tropical depression.

Tropical Depression Three will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Tropical Depression Three will move over water where where the Sea Surface Temperatures are near 29°C.  It will move under the eastern side of an upper level trough over the southeastern U.S.  The upper level trough will produce southwesterly winds that will blow toward the top of the tropical depression.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Depression Three is likely to intensify to a tropical storm during the next 24 hours.

The upper level trough over the Southeastern U.S. will steer Tropical Depression Three toward the north-northwest during the next 24 hours.  On its anticipated track, Tropical Depression Three will move toward the coast of South Carolina.  It could make landfall early on Sunday.

Tropical Depression Three is likely to strengthen to a tropical storm before it makes landfall.  It will bring winds and locally heavy rain.  Heavy rain could cause flash floods in some locations.

Tropical Storm Danas Forms Southwest of Taiwan

Tropical Storm Danas formed over the South China Sea southwest of Taiwan on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Danas was located at latitude 20.2°N and longitude 117.3°E which put the center about 265 miles (430 km) southwest of Kaohsiung, Taiwan.  Danas was moving toward the west 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.

A low pressure system over the South China Sea southwest of Taiwan strengthened on Friday and the Japan Meteorological Agency designated the system as Tropical Storm Danas.

The distribution of thunderstorms in Tropical Storm Danas was asymmetrical.  Thunderstorms were occurring in bands in the southern half of Danas’ circulation.  Bands in the northern half of Tropical Storm Danas consisted primarily of showers and lower clouds.  Storms near the center of Danas generated upper level divergence that pumped mass away to the south of the tropical storm.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Storm Danas was small.  Winds to tropical storm force extended out 70 miles (110 km) from the center of Danas’ circulation.

Tropical Storm Danas will move through an environment mostly favorable for intensification during the next 24 hours.  Danas will move over water where where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over eastern China.  The upper level ridge will produce northeasterly winds that will blow toward the top of Danas’ circulation.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Storm Danas will intensify during the next 24 hours.  Danas could strengthen to a typhoon during the weekend,

Tropical Storm Danas will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Danas toward the north during the next 24 hours.  On its anticipated track,  Tropical Storm Danas will move toward the Taiwan Strait.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Mun continued to meander southeast of Japan.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Mun was located at latitude 30.8°N and longitude 146.3°E which put the center about 485 miles (780 km) southeast of Tokyo, Japan.  Mun was moving toward the northeast at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 985 mb.

Tropical Storm Mun Spins Southeast of Japan

Tropical Storm Mun was spinning over the Western North Pacific Ocean southeast of Japan on Thursday evening.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Mun was located at latitude 29.9°N and longitude 144.9°E which put the center about 495 miles (795 km) southeast of Tokyo, Japan.  Mun was moving toward the north 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 982 mb.

Tropical Storm Mun strengthened on Thursday as it spun over the Western North Pacific Ocean southeast of Japan.  The circulation around Tropical Storm Mun became more symmetrical.  More thunderstorms developed near the center of Mun’s circulation.  Thunderstorms were also occurring in bands revolving around the center of Tropical Storm Mun.  Storms near the center of Mun generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Storm Mun was small.  Winds to tropical storm force extended out 60 miles (95 km) from the center of Mun’s circulation.

Tropical Storm Mun will move through an environment that will be favorable for intensification during the next 24 hours.  Mun will move over water where where the Sea Surface Temperatures are near 27°C.  An upper level low south of Japan will produce southwesterly winds that will blow toward the top of Mun’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear will probably not be enough to prevent intensification.  Tropical Storm Mun is likely to intensify during the next 24 hours.  Mun could strengthen to a typhoon.

Tropical Storm Mun will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mun toward the northeast during the next 24 hours.  On its anticipated track, Tropical Storm Mun will move farther away from Honshu.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 05W formed south of Taiwan.  At 11:00 p.m. EDT on Thursday the center of Tropical Depression 05W was located at latitude 19.7°N and longitude 118.6°E which put the center about 305 miles (495 km) south-southwest of Kaohsiung, Taiwan.  The tropical depression was moving toward the west-southwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1001 mb.

Hurricane Flossie Weakens Rapidly

Hurricane Flossie weakened rapidly on Wednesday evening as it moved over the Eastern North Pacific Ocean south of Baja California.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Flossie was located at latitude 19.8°N and longitude 110.2°W which put the center about 215 miles (345 km) south of Cabo San Lucas, Mexico.  Flossie was moving toward the northwest at 8 m.p.h. (13 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.

Hurricane Flossie was weakening rapidly on Wednesday evening as it moved over cooler water south of Baja California.  Many of the thunderstorms in Flossie’s circulation were dissipating,  The bands revolving around the center of Hurricane Flossie consisted primarily of showers and lower clouds.  The dissipation of the thunderstorms in Flossie greatly reduced the upper level divergence.  Much less mass was being pumped away from Hurricane Flossie.  The continued convergence of mass in the lower levels of Flossie’s circulation caused the surface pressure to increase quickly.

The circulation around Hurricane Flossie was small.  Winds to hurricane force extended out 25 miles (40 km) from the center of Flossie’s circulation.  Winds to tropical storm force extended out 70 miles (110 km) from the center of Hurricane Flossie.

Hurricane Flossie will move through an environment that will be unfavorable for intensification during the next 24 hours.  Flossie will move over water where where the Sea Surface Temperatures are near 23°C.  It will move under the middle of an upper level ridge over Mexico and the adjacent part of 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.  Even though there will be little vertical wind shear, the cooler water south of Baja California will cause Hurricane Flossie to continue to weaken on Thursday.

Hurricane Flossie will move around the southwestern part of a high pressure system over Mexico.  The high pressure system will steer the Flossie toward the northwest during the next 24 hours.  On its anticipated track, Hurricane Flossie will remain south of Baja California.

Tropical Storm Mun Forms Southeast of Japan

Tropical Storm Mun formed over the Western North Pacific Ocean southeast of Japan on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Mun was located at latitude 27.1°N and longitude 145.5°E which put the center about 680 miles (1100 km) south-southeast of Tokyo, Japan.  Mun was moving toward the northwest at 10 m.p.h. (16 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 1000 mb.

A low pressure system over the Western North Pacific Ocean southeast of Japan strengthened on Wednesday and the Japan Meteorological Agency designated the system as Tropical Storm Mun.

Tropical Storm Mun was under the eastern side of an upper level low southeast of Japan.  The upper level low was producing southwesterly winds that were blowing across the eastern part of Mun’s circulation.  Those winds were causing moderate vertical wind shear.  The vertical wind shear was causing the distribution of thunderstorms in Tropical Storm Mun to be asymmetrical.  Thunderstorms were occurring in bands in the western side of Mun’s circulation.  Bands in the eastern side of Tropical Storm Mun consisted primarily of showers and lower clouds.  Storms near the center of Mun generated upper level divergence that pumped mass away to the northeast of the tropical storm.

The vertical wind shear was also affecting the distribution of wind speeds in Tropical Storm Mun.  Winds to tropical storm force extended out 85 miles (135 km) in the northern side of Mun’s circulation.  Winds to tropical storm force extended out 40 miles (65 km) in the southern part of Tropical Storm Mun.

Tropical Storm Mun will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Mun will move over water where where the Sea Surface Temperatures are near 28°C.  However, the upper level low southeast of Japan will continue to cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification.  Tropical Storm Mun could intensify during the next 24 hours if the vertical wind shear does not increase.

The upper level low southeast of Japan will steer Tropical Storm Mun toward the north-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Mun will move toward eastern Japan.  Mun could meander east of Japan during the next few days.