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Typhoon Bavi Brings Wind and Rain to Ryukyu Islands

Typhoon Bavi brought wind and rain to the southern Ryukyu Islands on Friday.  At 11:00 p.m. EDT on Friday the center of Typhoon Bavi was located at latitude 25.6°N and longitude 124.1°E which put the center about 165 miles (265 km) east-northeast of Taipei, Taiwan.  Bavi was moving toward the north-northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 953 mb.

A weather station in Ishigakijima Island reported at sustained wind speed of 49 m.p.h. (80 km/h).  A weather station in Nakasuji, Japan reported a sustained wind speed of 53 m.p.h. (85 km/h).

Typhoon Bavi strengthened a little as it approached the southern Ryukyu Islands on Friday.  More thunderstorms formed near the center of Bavi’s circulation.  Concentric eyewalls appeared for a time on radar images from the Japan Meteorological Agency.  A small inner eye and eyewall was surrounded by a much larger outer eyewall that was a remnant from the last eyewall replacement cycle.

The distribution of thunderstorms in Typhoon Bavi continued to be asymmetrical.  Thunderstorms were occurring mostly in bands in the southern half of Bavi’s circulation.  Bands in the northern half of Typhoon Bavi consisted primarily of showers and lower clouds.  Storms near the center of Bavi generated more upper level divergence.  The removal of more mass caused the surface pressure to decrease on Friday.

Typhoon Bavi continued to be a very large typhoon.  Winds to typhoon force extended out 175 miles (280 km) from the center of Bavi’s circulation.  Winds to tropical storm force extended out 370 miles (595 km) from the center of Typhoon Bavi.

The Hurricane Intensity Index (HII) for Typhoon Bavi is 13.9.  The Hurricane Size Index (HSI) is 48.2 and the Hurricane Wind Intensity Size Index (HWISI) is 62.1.  Typhoon Bavi is similar in size and intensity to Hurricane Sandy when Sandy hit the east coast of the U.S. in 2012.

Typhoon Bavi will move through an environment that will be marginally favorable for intensification during the next 12 hours.  Bavi 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 Bavi will move through a region of drier air that is near eastern of Chin.a  The drier air will inhibit intensification.  Typhoon Bavi could maintain its intensity during the next 12 hours.

Typhoon Bavi 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 Bavi toward the northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Bavi will reach the east coast of China near Wenzhou in 12 hours.

Typhoon Bavi will bring strong winds and heavy rain to Zhejiang.  Heavy rain is likely to cause flash floods in some locations.  Typhoon Bavi could also cause a storm surge of up to 10 feet (3 meters) along parts of the east coast of China.

Typhoon Bavi Approaches Southern Ryukyu Islands

Typhoon Bavi was approaching the southern Ryukyu Islands on Thursday evening.  At 11:00 p.m. EDT on Thursday the center of Typhoon Bavi was located at latitude 21.3°N and longitude 126.9°E which put the center about 360 miles (580 km) southeast of Ishigakijima, Japan.  Bavi was moving toward the northwest at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (165 km/h).  The minimum surface pressure was 964 mb.

Typhoon Bavi weakened on Thursday when it moved into a region of drier air that was east of Taiwan.  The drier air caused many of the thunderstorms in the northern half of Bavi’s circulation to dissipate.  Bands in the northern side of Typhoon Bavi consisted primarily of showers and lower clouds.  Thunderstorms were still occurring in bands in the southern half of Bavi’s circulation.  Storms near the center of Bavi generated less upper level divergence.  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 continued to increase on Thursday.

The inner end of a rainband was wrapping back around the southern and eastern sides of the center of Typhoon Bavi on Thursday evening.  A new small eye appeared to be developing at the center of Bavi’s circulation.

Even though Typhoon Bavi weakened on Thursday, it continued to be a very large typhoon.  Winds to typhoon force extended out 185 miles (295 km) from the center of Bavi’s circulation.  Winds to tropical storm force extended out 370 miles (595 km) from the center of Typhoon Bavi.

The Hurricane Intensity Index (HII) for Typhoon Bavi is 12.7.  The Hurricane Size Index (HSI) is 57.5 and the Hurricane Wind Intensity Size Index (HWISI) is 70.2.  Typhoon Bavi is similar in intensity to Hurricane Sandy when Sandy hit the east coast of the U.S. in 2012.  Typhoon Bavi is larger than Hurricane Sandy was.

Typhoon Bavi will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Bavi 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 Bavi will continue to move through a region of drier air that is east of Taiwan.  The drier air will inhibit intensification, but drier air may have less of an effect on Friday.  Typhoon Bavi could intensify during the next 24 hours, especially if a new eye and eyewall develop at the center of Bavi’s circulation.

Typhoon Bavi 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 Bavi toward the northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Bavi will reach the southern Ryukyu Islands in 18 hours.  The center of Bavi will be near northeastern Taiwan in 24 hours.

Typhoon Bavi will bring strong winds and heavy rain to the southern Ryukyu Islands and to Taiwan.  Heavy rain is likely to cause flash floods in some locations.  Typhoon Bavi could cause a storms surge of up to 10 feet (3 meters) along the coast of the southern Ryukyu Islands and northern Taiwan.

Typhoon Bavi Moves Toward Southern Ryukyu Islands

Typhoon Bavi continued to move toward the southern Ryukyu Islands and Taiwan on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Bavi was located at latitude 18.6°N and longitude 129.6°E which put the center about 605 miles (975 km) southeast of Ishigakijima, Japan.  Bavi was moving toward the northwest at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 944 mb.

The cumulative effects of multiple eyewall replacement cycles caused Typhoon Bavi to weaken on Wednesday.  The most recent inner eyewall weakened and a much larger eye with a diameter of 70 miles (110 km) formed at the center of Bavi’s circulation.  The large 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 revolved around the center of Typhoon Bavi.  Storms near the center of Bavi generated less upper level divergence that pumped less mass away from the typhoon.  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 again on Wednesday.

The effects of the multiple eyewall replacement cycles also created a very large circulation around typhoon Bavi.  Winds to typhoon force extended out 160 miles (260 km) from the center of Bavi’s circulation.  Winds to tropical storm force extended out 335 miles (540 km) from the center of Typhoon Bavi.

The Hurricane Intensity Index (HII) for Typhoon Bavi is 23.6. The Hurricane Size Index (HSI) is 54.9 and the Hurricane Wind Intensity Size Index (HWISI) is 78.5.  Typhoon Bavi is similar in intensity to Hurricane Katrina when Katrina hit Mississippi in 2005.  Typhoon Bavi is much larger than Katrina was.

Typhoon Bavi will move through an environment that will be somewhat unfavorable for a powerful typhoon during the next 24 hours.  Bavi will move over water where the Sea Surface Temperatures are near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  However, Typhoon Bavi will move into a region of drier air that is east of Taiwan.  The drier air will inhibit the formation of new thunderstorms in the northwestern part of Bavi’s circulaiton.  Typhoon Bavi is likely to weaken slowly during the next 24 hours because of the drier air and the lingering effects of the eyewall replacement cycles.

Typhoon Bavi 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 Bavi toward the northwest during the next 24 hours.  On its anticipated track, Typhoon Bavi will approach the southern Ryukyu Islands in 36 hours.  The center of Bavi will be near northeastern Taiwan in 48 hours.

Typhoon Bavi will bring strong winds and heavy rain to the southern Ryukyu Islands and to Taiwan.  Heavy rain is likely to cause flash floods in some locations.  Typhoon Bavi could cause a storms surge of up to 12 feet (3.6 meters) along the coast of the southern Ryukyu Islands and northern Taiwan.

Typhoon Bavi Churns West

Typhoon Bavi continued to churn westward toward the southern Ryukyu Islands on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Typhoon Bavi was located at latitude 16.9°N and longitude 134.7°E which put the center about 975 miles (1575 km) east-southeast of Ishigakijima, Japan.  Bavi was moving toward the west at 14 m.p.h. (22 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 927 mb.

Typhoon Bavi completed another eyewall replacement cycle on Tuesday.  An circular eye with a diameter of 45 miles (75 km) was at the center of Bavi’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 revolved around the center of Typhoon Bavi.  Storms near the center of Bavi generated upper level divergence that pumped mass away from the typhoon. The removal of mass in the upper levels was nearly equal to the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure did not change much on Tuesday.

There was a large circulation around Typhoon Bavi.  Winds to typhoon force extended out 105 miles (165 km) from the center of Bavi’s circulation.  Winds to tropical storm force extended out 310 miles (500 km) from the center of Typhoon Bavi.

The Hurricane Intensity Index (HII) for Typhoon Bavi is 31.6.  The Hurricane Size Index (HSI) is 37.9 and the Hurricane Wind Intensity Size Index (HWISI) is 69.5. Typhoon Bavi is similar in intensity to Hurricane Laura when Laura hit Southwest Louisiana in 2020.  Typhoon Bavi is much larger than Laura was.

Typhoon Bavi will more through an environment that will be favorable for a powerful typhoon during the next 24 hours.  Bavi will move over water where the Sea Surface Temperatures are near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Bavi could maintain its intensity during the next 24 hours unless another eyewall replacement cycle occurs.

Typhoon Bavi 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 Bavi toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Bavi will approach the southern Ryukyu Islands and Taiwan in less than 72 hours.

Tropical Storm Mekkhala Nears Southern Ryukyu Islands

Tropical Storm Mekkhala was nearing the southern Ryukyu Islands on Wednesday night.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Mekkhala was located at latitude 24.1°N and longitude 125.6°E which put the center about 45 miles (75 km) south of Miyakojima, Japan.  Mekkhala was moving toward the north-northeast at 13 m.p.h. (21 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 986 mb.

Former Typhoon Mekkhala weakened to a tropical storm as it approached the southern Ryukyu Islands on Wednesday.  An upper level ridge over China continued to produce northeasterly winds that blew toward the top of Mekkhala’s circulation.  Those winds caused strong vertical wind shear.  The strong vertical wind shear caused former Typhoon Mekkhala to weaken to a tropical storm.

The northeasterly winds in the upper levels also continued to blow the tops off of many of the thunderstorms that tried to form in the northern half of Tropical Storm Mekkhala.  A few more thunderstorms did develop near the center of Mekkhala’s circulation.  Thunderstorms were also occurring in bands in the southern half of Tropical Storm Mekkhala.  Bands in the northern half of Mekkhala still consisted primarily of showers and lower clouds.  Storms near the center of Mekkhala generated upper level divergence that pumped mass away to the south and west of the typhoon.  However, 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 continued to increase on Wednesday.

The size of the circulation around Tropical Storm Mekkhala increased a little on Wednesday.  Winds to tropical storm force extended out 165 miles (265 km) from the center of Mekkhala’s circulation.

Tropical Storm Mekkhala will move through an environment that will be unfavorable for intensification during the next 24 hours.  Mekkhala will move over water where the Sea Surface Temperatures are near 27°C.  However, the upper level ridge over China will continue to cause vertical wind shear.  The vertical wind shear may be a little less on Thursday.  Tropical Storm Mekkhala could maintain its intensity during the next 24 hours if the vertical wind shear is a little less.

Tropical Storm Mekkhala will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mekkhala toward the northeast during the next 24 hours.  On its anticipated track, Tropical Storm Mekkhala will pass over Miyakojima during the next few hours.  Mekkhala could be near Okinawa in 12 hours.

Tropical Storm Mekkhala will bring strong winds and locally heavy rain to the southern Ryukyu Islands including Ishigakijima and Miyakojima.  Heavy rain could cause flash floods in some locations.  Mekkhala will also bring gusty winds and locally heavy rain to Okinawa.

Elsewhere over the Western North Pacific Ocean, former Tropical Depression Higos strengthened back to a tropical storm on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Higos was located at latitude 18.3°N and longitude 137.1°E which put the center about 540 miles (870 km) south-southwest of Iwo To.  Higos was moving toward the northwest at 14 m.p.h. (22 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.

Typhoon Mekkhala Weakens

Typhoon Mekkhala weakened on Tuesday as it moved toward the southern Ryukyu Islands.  At 11:00 p.m. EDT on Tuesday the center of Typhoon Mekkhala was located at latitude 21.3°N and longitude 124.7°E which put the center about 235 miles (380 km) south of Miyakojima, Japan.  Mekkhala was moving toward the north at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (165 km/h).  The minimum surface pressure was 974 mb.

Typhoon Mekkhala weakened on Tuesday.  An upper level ridge over China produced northeasterly winds that blew toward the top of Mekkhala’s circulation.  Those winds caused strong vertical wind shear.  The strong vertical wind shear caused Typhoon Mekkhala to weaken.

The northeasterly winds in the upper levels also blew the tops off of many of the thunderstorms in the northern half of Typhoon Mekkhala.  Thunderstorms were still occurring in bands in the southern half of Mekkhala’s circulation.  Bands in the northern half of Typhoon Mekkhala consisted primarily of showers and lower clouds.  Storms near the center of Mekkhala generated upper level divergence that pumped mass away to the south and west of the typhoon.  However, 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 Tuesday.

Even though Typhoon Mekkhala weakened on Tuesday, the size of Mekkhala’s circulation did not change much.  Winds to typhoon force extended out 65 miles (105 km) from the center of Typhoon Mekkhala.  Winds to tropical storm force extended out 140 miles (225 km) from the center of Mekkhala’s circulation.

Typhoon Mekkhala will move through an environment that will be unfavorable for intensification during the next 24 hours.  Mekkhala will move over water where the Sea Surface Temperatures are near 28°C.  However, the upper level ridge over China will continue to cause strong vertical wind shear.  Typhoon Mekkhala will continue to weaken during the next 24 hours because of the strong vertical wind shear.

Typhoon Mekkhala will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mekkhala toward the north during the next 24 hours.  On its anticipated track, Typhoon Mekkhala will reach the southern Ryukyu Islands in less than 24 hours.

Typhoon Mekkhala will bring strong winds and locally heavy rain to the southern Ryukyu Islands including Ishigakijima and Miyakojima.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, former Tropical Storm Higos weakened to a tropical depression as it moved west of the Marianas.  At 11:00 p.m. EDT on Tuesday the center of Tropical Depression Higos was located at latitude 15.4°N and longitude 141.3°E which put the center about 225 miles (360 km) west-northwest of Guam.  Higos was moving toward the west-northwest at 11 m.p.h. (17 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 1002 mb.

Tropical Storm Prapiroon Brings Wind and Rain to Hainan

Tropical Storm Prapiroon brought wind and rain to Hainan on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Prapiroon was located at latitude 19.1°N and longitude 109.9°E which put the center about 65 miles (105 km) south-southwest of Haikou, China.  Prapiroon was moving toward the northwest at 13 m.p.h. (21 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 992 mb.

Tropical Storm Prapiroon intensified on Sunday before the center moved over Hainan.  Microwave satellite images indicated that an eye was in the process of forming at the center of Prapiroon’s circulation as the tropical storm made landfall in Hainan.  The formative eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Prapiroon.

Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Storm Prapiroon.

The center of Tropical Storm Prapiroon made landfall on the south coast of Hainan near Lingshui.  The core of Prapiroon’s circulation moved across the center of Hainan.  Storms near the center of Tropical Storm Prapiroon brought heavy rain and strong winds to much of Hainan.  Bands in the northern part of Hainan’s circulation were also bringing gusty winds and heavy rain to parts of southern China.

Tropical Storm Prapiroon will move around the southern side of a high pressure system over southern China.  The high pressure system will steer Prapiroon toward the northwest during the next 24 hours.  On its anticipated track Tropical Storm Prapiroon will move over the Gulf of Tonkin on Monday.  The center of Prapiroon’s circulation could approach the southern coast of China in 24 hours.

Tropical Storm Prapiroon will continue to cause strong winds and locally heavy rain in Hainan during the next few hours.  Heavy rain could cause flash floods in some locations.  Prapiroon will also bring gusty winds and heavy rain to parts of southern China and northeastern Vietnam.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Gaemi strengthened east of Luzon.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Gaemi was located at latitude 17.2°N and longitude 125.7°E which put the center about 525 miles (845 km) south of Ishigakijima, Japan.  Gaemi was moving toward the north-northwest at 3 m.p.h. (5 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 992 mb.

Tropical Storm Prapiroon Forms Over South China Sea

Tropical Storm Prapiroon formed over the South China Sea on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Prapiroon was located at latitude 16.3°N and longitude 111.2°E which put the center about 260 miles (460 km) south-southeast of Haikou, China.  Prapiroon was moving toward the west 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 998 mb.

Former Tropical Depression 04W strengthened on Saturday night and the Japan Meteorological Agency designated the system as Tropical Storm Prapiroon.  The circulation around Tropical Storm Prapiroon was exhibiting a little more organization.  There were not a lot of thunderstorms near the center of Prapiroon’s circulation.  Thunderstorms were occurring in bands revolving around the center of Tropical Storm Prapiroon.

Although the circulation around Tropical Storm Prapiroon was large, the area of stronger winds was relatively small.  Winds to tropical storm force extended out 60 miles (95 km) from the center of Prapiroon’s circulation.

Tropical Storm Prapiroon will move through an environment somewhat favorable for intensification during the next 24 hours.  Prapiroon will move over water where the Sea Surface Temperatures are near 30°C.   It will move under the southeastern part of an upper level ridge over China.  The upper level ridge will produce northeasterly winds that will blow toward the top of Prapiroon’s circulation.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification but the shear may not be strong enough to prevent some strengthening.  Tropical Storm Prapiroon could intensify a little during the next 24 hours.

Tropical Storm Prapiroon will move around the southern part of a high pressure system over eastern China.  The high pressure system will steer Prapiroon toward the northeast during the next 24 hours.  On its anticipated track Tropical Storm Prapiroon will move toward Hainan.

Tropical Storm Prapiroon will bring gusty winds and heavy rain to Hainan during the next 24 hours.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Gaemi strengthened gradually east of the Philippines.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Gaemi was located at latitude 17.0°N and longitude 125.5°E which put the center about 485 miles (780 km) south of Ishigakijima, Japan.  Gaemi was moving toward the west-northwest at 9 m.p.h. (15 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 996 mb.

Tropical Storm Gaemi Forms East of the Philippines

Tropical Storm Gaemi formed over the Western North Pacific Ocean east of the Philippines early on Saturday.   At 5:00 a.m. EDT on Saturday the center of Tropical Storm Gaemi was located at latitude 16.1°N and longitude 128.2°E which put the center about 520 miles (840 km) south-southeast of Ishigakijima, Japan.  Gaemi was moving toward the 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 1002 mb.

A low pressure system over the Western North Pacific Ocean east of the Philippines strengthened early on Saturday and the Japan Meteorological Agency designated the system as Tropical Storm Gaemi.  The circulation around Tropical Storm Gaemi was starting to exhibit more organization.  More thunderstorms were forming near the center of Gaemi’s circulation.  Thunderstorms were also developing in bands revolving around the center of Tropical Storm Gaemi.  Storms near the center of Gaemi started to generate upper level divergence that pumped mass away from the tropical storm.

Tropical Storm Gaemi will move through an environment favorable for intensification during the next 24 hours.  Gaemi will move over water where the Sea Surface Temperatures are near 30°C.   It will move under the western part of an upper level ridge over the Western North Pacific Ocean.  The upper level ridge will produce southeasterly winds that will blow toward the top of Gaemi’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Storm Gaemi is likely to intensify gradually during the next 24 hours.  Gaemi could strengthen to a typhoon by early next week.

Tropical Storm Gaemi will move around the western part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Gaemi toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Gaemi will move toward the southern Ryukyu Islands.  Gaemi could be a typhoon when it approaches the southern Ryukyu Islands early next week.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 04W formed over the South China Sea.  At 5:00 a.m. EDT on Saturday the center of Tropical Depression 04W was located at latitude 16.1°N and longitude 113.8°E which put the center about 360 miles (580 km) southeast of Haikou, China.   The tropical depression was moving toward the northwest 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 999 mb.

Typhoon Mawar Moves South of Ryukyu Islands

Typhoon Mawar moved south of the Ryukyu Islands on Sunday morning. At 5:00 a.m. EDT on Sunday the center of Typhoon Mawar was located at latitude 17.7°N and longitude 125.7°E which put it about 505 miles (815 km) southeast of Ishigakijima, Japan. Mawar was moving toward the west-northwest at 11 m.p.h. (17 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 951 mb.

Typhoon Mawar continued to weaken gradually on Sunday morning as it moved over the Western North Pacific Ocean south of the Ryukyu Islands. A circular eye with a diameter of 20 miles (32 km) was present at the center of Mawar’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Numerous bands of showers and thunderstorms were revolving around the center of Typhoon Mawar. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm in all directions. The upper level divergence was still not removing as much mass as was converging in the lower levels of Mawar’s circulation which caused the surface pressure to continue to increase slowly.

Typhoon Mawar continued to be a large typhoon even though it was gradually weakening. Winds to typhoon force extended out 80 miles (130 km) from the center of Mawar’s circulation. Winds to tropical storm force extended out 250 miles (400 km) from the center of Mawar. The Hurricane Intensity Index (HII) for Typhoon Mawar was 22.1. The Hurricane Size Index (HSI) was 26.6 and the Hurricane Wind Intensity Size Index (HWISI) was 48.7. Typhoon Mawar was similar in size and intensity to Hurricane Jeanne when Jeanne hit South Florida in 2004.

Typhoon Mawar will move through an environment favorable for a strong typhoon during the next 24 hours. Mawar will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the the axis of an upper level ridge over the Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Although the environment is favorable, Typhoon Mawar will continue to weaken gradually as long as the upper level divergence is removing less mass than is converging in the lower levels. Typhoon Mawar is forecast to continue to weaken during the next 24 hours.

Typhoon Mawar will move around the southwestern part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar toward the west-northwest during the next 24 hours. Typhoon Mawar will move toward the north when it reaches the western end of the high pressure system early next week. On its anticipated track, Typhoon Mawar will move toward the southern Ryukyu Islands next week.