Category Archives: Tropical Cyclones

Information about tropical cyclones

Tropical Storm Mitag Develops Southeast of Hong Kong

Tropical Storm Mitag developed over the South China Sea southeast of Hong Kong on Thursday morning.  At 11:00 a.m. EDT on Thursday the center of Tropical Storm Mitag was located at latitude 20.4°N and longitude 116.5°E which put the center about 225 miles (365 km) southeast of Hong Kong.  Mitag was moving toward the west-northwest at 6 m.p.h. (10 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 1002 mb.

A low pressure system over the South China Sea southeast of Hong Kong strengthened on Thursday morning and the Japan Meteorological Agency  designated the system as Tropical Storm Mitag.

The circulation around Tropical Storm Mitag continued to get better organized on Thursday morning.  More thunderstorms formed near the center of Mitag’s circulation.  Thunderstorms also developed in bands in the eastern side of Tropical Storm Mitag.  Bands in the western side of Mitag’s circulation still consisted primarily of showers and lower clouds.

The strongest winds were occurring in the eastern side of Tropical Storm Mitag.  Winds to tropical storm force extended out 80 miles (130 km) in the eastern side of Mitag’s circulation.  The winds in the western side of Tropical Storm Mitag were blowing at less than tropical storm force.

Tropical Storm Mitag will move through an environment favorable for intensification during the next 24 hours.  Mitag will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge over eastern China and the South China Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Storm Mitag will intensity during the next 24 hours.

Tropical Storm Mitag will move around the southwestern part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mitag toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Mitag will be near Hong Kong in 24 hours.

Tropical Storm Mitag will bring strong winds and locally heavy rain to the region around Hong Kong.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Ragasa formed east of Luzon and Tropical Storm Neoguri formed southeast of Japan.

At 11:00 a.m. EDT on Thursday the center of Tropical Storm Ragasa was located at latitude 16.0°N and longitude 132.7°E which put the center about 755 miles (1220 km) east of Aparri, Philippines.  Ragasa was moving toward the northwest at 5 m.p.h. (8 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.

At 11:00 a.m. EDT on Thursday the center of Tropical Storm Neoguri was located at latitude 23.1°N and longitude 162.5°E which put the center about 1630 miles (2630 km) east-southeast of Tokyo, Japan.  Neoguri was moving toward the west-southwest at 13 m.p.h. (21 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.

Tropical Storm Gabrielle Forms East of Leeward Islands

Tropical Storm Gabrielle formed over the Atlantic Ocean east of the Leeward Islands on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Gabrielle was located at latitude 17.5°N and longitude 46.6°W which put the center about 1085 miles (1745 km) east of the Northern Leeward Islands.  Gabrielle was moving toward the north-northwest at 22 m.p.h. (35 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 1006 mb.

A low pressure system over the Atlantic Ocean east of the Northern Leeward Islands strengthened on Tuesday morning and the U.S. National Hurricane Center designated the system as Tropical Storm Gabrielle.

The circulation around Tropical Storm Gabrielle was poorly organized on Thursday morning.  Thunderstorms were occurring in bands east of the center of Gabrielle’s circulation.  Bands in the western part of Tropical Storm Gabrielle consisted primarily of showers and lower clouds.  An upper level low northeast of the Leeward Islands was producing strong southwesterly winds that were blowing toward the top of Gabrielle’s circulation.  Those winds were causing strong vertical wind shear.  The strong vertical wind shear was causing the asymmetrical distribution of thunderstorms in Tropical Storm Gabrielle.

The distribution of wind speeds in Tropical Storm Gabrielle was also asymmetrical.  Winds to tropical storm force extended out 175 miles (280 km) in the eastern side of Gabrielle’s circulation.  The winds in the western side of Tropical Storm Gabrielle were blowing at less than tropical storm force.

Tropical Storm Gabrielle will move through an environment that will be only marginally favorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 28°C.   However, the upper level low that is northeast of the Northern Leeward Islands will continue to cause strong vertical wind shear.  The strong vertical wind shear will prevent significant intensification during the next 24 hours.

Tropical Storm Gabrielle will move around the southwestern part of a subtropical high pressure system over the eastern Atlantic Ocean.  The high pressure system will steer Gabrielle toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Gabrielle will pass northeast of the Leeward Islands later this week.

 

Tropical Storm Mario Weakens

Tropical Storm Mario weakened on Monday night as it moved over the Eastern North Pacific Ocean west of Baja California.  At 5:00 a.m. EDT on Tuesday the center of Tropical Storm Mario was located at latitude 21.9°N and longitude 115.7°W which put the center about 375 miles (605 km) west of the southern tip of Baja California.  Mario was moving toward the northwest at 12 m.p.h. (19 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.

Tropical Storm Mario weakened on Monday night as it moved over cooler water west of Baja California.  Many of the thunderstorms in Tropical Storm Mario dissipated when Mario moved over the cooler water.  A few thunderstorms were still occurring near the center of Mario’s circulation.  Most of the bands revolving around the center of Tropical Storm Mario consisted primarily of showers and lower clouds.  Since the storms near the center of Mario were not generating much upper level divergence, the surface pressure was increasing.

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

Tropical Storm Mario will move through an environment that will be unfavorable for intensification during the next 24 hours.  Mario 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 is near the west coast of the U.S.  The upper level trough will produce southerly winds that will blow toward the top of Mario’s circulation.  Those winds will cause moderate vertical wind shear.  The combination of moderate vertical wind shear and cooler Sea Surface Temperatures will cause Tropical Storm Mario to continue to weaken during the next 24 hours.

Tropical Storm Mario will move around the around the southwestern part of a high pressure system over the southwest U.S. and northwest Mexico.  The high pressure system will steer Mario toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Mario will move west of Baja California.

Tropical Storm Mario Strengthens

Tropical Storm Mario strengthened during Sunday night as it moved over the Eastern North Pacific Ocean south of Baja California.  At 5:00 a.m. EDT on Monday the center of Tropical Storm Mario was located at latitude 19.4°N and longitude 112.3°W which put the center about 285 miles (460 km) south-southwest of the southern tip of Baja California.  Mario was moving toward the west-northwest at 12 m.p.h. (19 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 995 mb.

Tropical Storm Mario strengthened during Sunday night.  The distribution of thunderstorms in Mario became more symmetrical.  Thunderstorms continued to develop near the center of Mario’s circulation.  Thunderstorms were also occurring in bands revolving around the center of Tropical Storm Mario.  Storms near the center of Mario generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

Even though Tropical Storm Mario strengthened, the size of Mario’s circulation remained small.  Winds to tropical storm force extended out 35 miles (55 km) from the center of Tropical Storm Mario.

Tropical Storm Mario will move through an environment that will become unfavorable for intensification during the next 24 hours.  Mario will move over water where the Sea Surface Temperatures are near 26°C.  It will move under the southeastern part of an upper level trough  that is near the west coast of the U.S.  The upper level trough will produce southwesterly winds that will blow toward the top of Mario’s circulation.  Those winds will cause the vertical wind shear to increase.  The combination of more vertical wind shear and cooler Sea Surface Temperatures will cause Tropical Storm Mario to start to weaken during the next 24 hours.

Tropical Storm Mario will move around the around the southern part of a high pressure system over the southwest U.S. and northwest Mexico.  The high pressure system will steer Mario toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Mario will remain southwest of Baja California.

Tropical Storm Mario Re-develops South of Baja California

Tropical Storm Mario re-developed over the Eastern North Pacific Ocean south of Baja California on Sunday morning.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Mario was located at latitude 18.5°N and longitude 110.2°W which put the center about 305 miles (490 km) south of the southern tip of Baja California.  Mario was moving toward the west-northwest at 8 m.p.h. (13 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 1004 mb.

After almost dissipating during Friday night, Tropical Storm Mario re-developed south of Baja California on Sunday morning.  A distinct low level center of circulation re-formed on Sunday morning.  More thunderstorms started to develop near the low level center of circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Mario.  Storms near the center of Mario began to generate upper level divergence that pumped mass away from the tropical storm.

The circulation around Tropical Storm Mario was still small.  Wind to tropical storm force extended out 25 miles (40 km) in the northeastern quadrant of Mario’s circulation.  The winds in the other parts of Tropical Storm Mario were blowing at less than tropical storm force.

Tropical Storm Mario will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Mario will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southeastern part of upper level ridge over the southwest U.S. and northwest Mexico.  The upper level ridge will produce northeasterly winds that will blow toward the top of Mario’s circulation.  Those winds will cause moderate vertical wind shear.  The moderate vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Tropical Storm Mario is likely to intensify during the next 24 hours.

Tropical Storm Mario will move around the around the southern part of a high pressure system over the southwest U.S. and northwest Mexico.  The high pressure system will steer Mario toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Mario will southwest of Baja California.

 

Tropical Storm Mario Forms Near Zihuatanejo

Tropical Storm Mario formed over the Eastern North Pacific Ocean near Zihuatanejo, Mexico on Friday morning.  The government of Mexico issued a Tropical Storm Watch for a portion of the coast.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Mario was located at latitude 17.2°N and longitude 101.9°W which put the center about 40 miles (65 km) south-southwest of Zihuatanejo, Mexico.  Mario 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 1006 mb.

A Tropical Storm Watch is in effect for the portion of the coast from Lazaro Cardenas to Punta San Telmo, Mexico.

A low pressure system over the Eastern North Pacific Ocean near Zijuatanejo strengthened on Friday morning and the U.S. National Hurricane Center designated the system as Tropical Storm Mario.

The circulation around Tropical Storm Mario exhibited more organization on Friday morning.  More thunderstorms developed near the center of Mario’s circulation.  Thunderstorms were also occurring in short bands that were revolving around the center of Tropical Storm Mario.  Storms near the center of Mario generated upper level divergence that pumped mass away from the tropical storm.

The circulation around Tropical Storm Mario was very small.  Winds to tropical storm force extended out 25 miles (40 km) in the northwestern quadrant of Mario’s circulation.  The winds in the other parts of Tropical Storm Mario were blowing at less than tropical storm force.

Tropical Storm Mario will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Mario will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the southern part of upper level ridge over Mexico.  The upper level ridge will produce northeasterly winds that will blow toward the top of Mario’s circulation.  Those winds will cause moderate vertical wind shear.  The circulation around Tropical Storm Mario could also pull drier air over Mexico in the tropical storm.  The moderate vertical wind shear and drier air will inhibit intensification.  Tropical Storm Mario could intensify during the next 24 hours if the center remains over the ocean.

Tropical Storm Mario will move around the around the southwestern part of a high pressure system over Mexico.  The high pressure system will steer Mario toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Mario will move near the coast of Michoacan.

Tropical Storm Mario will bring gusty winds and locally heavy rain to coastal parts of Michoacan.  Heavy rain could cause flash floods in some locations.

Kiko Weakens to a Tropical Storm

Former Hurricane Kiko weakened to a tropical storm over the Central Pacific Ocean northeast of Hawaii on Monday night.  At 5:00 a.m. EDT on Tuesday the center of Tropical Storm Kiko was located at latitude 21.9°N and longitude 152.1°W which put the center about 245 miles (395 km) northeast of Hilo Hawaii.  Kiko was moving toward the west-northwest at 14 m.p.h. (22 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 1004 mb.

Former Hurricane Kiko weakened to a tropical storm over the Central Pacific Ocean northeast of Hawaii during Monday night.  An upper level low that is north of Hawaii produced strong southwesterly winds that blew across the top of Kiko’s circulation.  Those winds caused strong vertical wind shear.  The strong vertical wind shear caused Kiko to weaken to a tropical storm.

The strong upper level winds blew the tops off of most of the thunderstorms in Tropical Storm Kiko.  A few thunderstorms remained in the far northeastern periphery of Kiko’s circulation.  Most of the bands revolving around the center of Tropical Storm Kiko consisted of showers and lower clouds.  Since there were no thunderstorms near the center of Kiko to pump mass away, the surface pressure increased rapidly.

The size of the circulation around Tropical Storm Kiko expanded a little as Kiko weakened.  Winds to tropical storm force extended out 125 miles (200 km) from the center of Kiko’s circulation.

Tropical Storm Kiko will move through an environment unfavorable for intensification during the next 24 hours.  Kiko will move over water where the Sea Surface Temperatures are near 27°C.  However, the upper low north of Hawaii will continue to cause strong vertical wind shear.  The strong vertical wind shear will cause Tropical Storm Kiko to continue to weaken.

Tropical Storm Kiko will move around the southern side of a high pressure system over the Central Pacific Ocean.  The high pressure system will steer Kiko toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Kiko will pass north of Hawaii.

 

Typhoon Tapah Brings Wind and Rain to Southern China

Typhoon Tapah brought wind and rain to southern China on Sunday night.  At 11:00 p.m. EDT on Sunday the center of Typhoon Tapah was located at latitude 22.2°N and longitude 112.2°E which put the center about 75 miles (120 km) west of Macau.  Tapah was moving toward the north-northwest at 13 m.p.h. (21 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 984 mb.

Former Tropical Storm Tapah strengthened to a typhoon just before it made landfall on the coast of southern China on Sunday night.  The center of Typhoon Tapah made landfall about 75 miles (120 km) west of Macau.

The strongest winds in Typhoon Tapah were occurring in the southern part of Tapah’s circulation which was still over the South China Sea.  Winds to typhoon force extended out 40 miles (65 km) in the southern half of Typhoon Tapan.  Winds to tropical storm force extended out 120 miles (195 km) from the center of Tapah’s circulation.

Typhoon Tapah will move around the southwestern side of a high pressure system over China.  The high pressure system will steer Tapah toward the northwest during the next 24 hours.  On its anticipated track, Typhoon Tapah will move inland over Guangdong and Guangxi.

Typhoon Tapah will bring strong winds and heavy rain to southwestern Guangdong.  Heavy rain is likely to cause floods in some locations.  Typhoon Tapah will weaken steadily as it move inland over southern China.  Tapah will also bring gusty winds and locally heavy rain to parts of Guangxi.

 

Hurricane Kiko Weakens

Hurricane Kiko weakened east of Hawaii on Sunday.  At 5:00 p.m. EDT on Sunday the center of Hurricane Kiko was located at latitude 18.1°N and longitude 145.5°W which put the center about 635 miles (1025 km) east of Hilo Hawaii. Kiko was moving toward the west-northwest at 13 m.p.h. (21 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 974 mb.

Hurricane Kiko weakened east of Hawaii on Sunday as it moved over water where the Sea Surface Temperature was near 26°C.  A circular eye was still present at the center of Kiko’s circulation, but low clouds were starting to appear inside the eye.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Storms near the center of Kiko generated upper level divergence that pumped mass away from the hurricane.  However, more mass was converging in the lower levels of the atmosphere than was being pumped away in the upper levels.  So, the surface pressure was increasing.

The circulation around Hurricane Kiko was small.  Winds to hurricane force extended out 30 miles (50 km) from the center of Kiko’s circulation.  Winds to tropical storm force extended out 80 miles (130 km) from the center of Hurricane Kiko.

The Hurricane Intensity Index (HII) for Hurricane Zeta was 19.2.  The Hurricane Size Index (HSI) was 9.1 and the Hurricane Wind Intensity Size Index (HWISI) was 28.3. Hurricane Kiko was similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

Hurricane Kiko will move through an environment that will become even more unfavorable for intensification during the next 24 hours.  Kiko will move over water where the Sea Surface Temperatures are near 26°C.  The water just to the north of Kiko’s forecast track is even colder. It will move under the southeastern part of an upper level low that is north of Hawaii.  The upper level low will produce southwesterly winds that will blow toward the top of Kiko’s circulation.  Those winds will cause the vertical wind shear to increase.  The combination of marginal Sea Surface Temperatures and more vertical wind shear will cause Hurricane Kiko to continue to weaken during the next 24 hours.

Hurricane Kiko will move around the southwestern part of a high pressure system over the Eastern North Pacific Ocean.  The high pressure system will steer Kiko toward the west-northwest during the next 24 hours.  On its anticipated track, Hurricane Kiko will be northeast of Hawaii on Monday night.

Tropical Storm Tapah Nears Southern China

Tropical Storm Tapah was nearing the coast of southern China on Sunday.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Tapah was located at latitude 20.4°N and longitude 113.4°E which put the center about 75 miles (120 km) south of Macau.  Tapah was moving toward the north-northwest 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 991 mb.

Tropical Storm Tapah was strengthening as it neared the coast of southern China on Sunday.  The inner end of a rainband wrapped around the eastern side of the center of Tapah’s circulation.  An eye appeared to be forming at the center of Tropical Storm Tapah.  Bands of showers and thunderstorms were revolving around the center of Tapah’s circulation.  Storms near the center of Tapah generated upper level divergence that pumped mass away to the southwest of the tropical storm.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Storm Tapah became more symmetrical on Sunday.  Winds to tropical storm force extended out 120 miles (195 km) from the center of Tapah’s circulation.

Tropical Storm Tapah will move through an environment favorable for intensification during the next 12 hours.  Tapah 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 northeasterly winds that will blow toward the top of Tapah’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Storm Tapah will intensify during the next 12 hours.  Tapah could strengthen to a typhoon before it reaches the coast of southern China.

Tropical Storm Tapah will move around the southwestern side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Tapah toward the northwest during the next 12 hours.  On its anticipated track, Tropical Storm Tapah will make landfall on the coast of southern China west of Macau in 12 hours.

Tropical Storm Tapah could intensify to a typhoon before it makes landfall on the coast of southern China.  Tapah will bring strong winds and heavy rain to southwestern Guangdong.  Heavy rain is likely to cause floods in some locations.