Depression Strengthens to Tropical Storm Douglas

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Former Tropical Depression 04E strengthened to Tropical Storm Douglas on Wednesday afternoon as it moved over the Eastern North Pacific Ocean southwest of Baja California.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Douglas was located at latitude 15.7°N and longitude 127.0°W which put the center about 1220 miles (1960 km) west-southwest of the southern tip of Baja California.  Douglas was moving toward the north at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1003 mb.

Former Tropical Depression 04E strengthened on Wednesday afternoon and the U.S. National Hurricane Center designated the system as Tropical Storm Douglas.

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

The strongest winds were occurring in the eastern side of Tropical Storm Douglas.  Winds to tropical storm force extended out 90 miles (145 km) in the eastern side of Douglas’ circulation.  The winds in the western half of Tropical Storm Douglas were blowing at less than tropical storm force.

Tropical Storm Douglas will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Douglas will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the western part of an upper level ridge that is southwest of Baja California.  The upper level ridge will produce southwesterly winds that will blow toward the top of Douglas’ circulation.  Those winds will cause moderate vertical wind shear.  There is also some drier air north and west of Tropical Storm Douglas.  The drier air could limit the development of thunderstorms in those parts of Douglas’ circulation.  Tropical Storm Douglas could intensify a little more during the next 24 hours, if the drier air does not get pulled into the center of its circulation.  Douglas is likely to move over cooler water by later on Thursday.

Tropical Storm Douglas will move around the southwestern part of a high pressure system that is over the Eastern North Pacific Ocean.  The high pressure system will steer Douglas toward the north-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Douglas will remain far to the southwest of Baja California.

Tropical Depression 04E Forms Southwest of Baja California

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Tropical Depression 04E formed over the Eastern North Pacific Ocean southwest of Baja California on Tuesday night.  At 5:00 a.m. EDT on Wednesday the center of Tropical Depression 04E was located at latitude 14.5°N and longitude 126.9°W which put the center about 1250 miles (2015 km) west-southwest of the southern tip of Baja California.  The tropical depression was moving toward the north-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 1005 mb.

A low pressure system over the Eastern North Pacific Ocean southwest of Baja California strengthened on Tuesday night and the U.S. National Hurricane Center designated the system as Tropical Depression 04E.

The distribution of thunderstorms in Tropical Depression 04E was asymmetrical.  Thunderstorms were occurring in bands in the southern and eastern parts of the tropical depression.  Bands in the northern and western parts of Tropical Depression 04E consisted primarily of showers and lower clouds.  Storms near the center of circulation began to generate upper level divergence that pumped mass away from the tropical depression.

Tropical Depression 04E will move through an environment that will be mostly favorable for intensification during the next 24 hours.  The tropical depression will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the middle of an upper level ridge that is southwest of Baja California.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  There is some drier air north and west of the tropical depression.  The drier air could limit the development of thunderstorms in those parts of the tropical depression.  Tropical Depression 04E could intensify to a tropical storm if the drier air does not get pulled into the center of its circulation.

Tropical Depression 04E will move around the southwestern part of a high pressure system that is over the Eastern North Pacific Ocean.  The high pressure system will steer the tropical depression toward the north-northwest during the next 24 hours.  On its anticipated track, Tropical Depression 04E will remain far to the southwest of Baja California.

Tropical Depression Forms East-southeast of Marianas

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Tropical Depression 09W formed over the Western North Pacific Ocean east-southeast of the Marianas on Tuesday evening.  At 11:00 p.m. EDT on Tuesday the center of Tropical Depression 09W was located at latitude 8.9°N and longitude 162.9°E which put the center about 175 miles (280 km) east-southeast of Ujelang.  The tropical depression was moving toward the west at 12 m.p.h. (19 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 1003 mb.

A low pressure system over the Western North Pacific Ocean east-southeast of the Marianas strengthened on Tuesday evening.  Both the Japan Meteorological Agency and the U.S. Joint Typhoon Warning Center classified the system as a tropical depression.

More thunderstorms formed near the center of Tropical Depression 09W on Tuesday evening.  Thunderstorms were also developing in bands in the northern and western parts of the tropical depression.  Bands in the southern and eastern parts of Tropical Depression consisted primarily of showers and lower clouds.  Storms near the center of circulation began to generate upper level divergence that pumped mass away to the west of the tropical depression.  The removal of mass caused the surface pressure to start to decrease.

Tropical Depression 09W will move through an environment favorable for intensification during the next 24 hours.  The tropical depression will move over water where the Sea Surface Temperatures are near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Depression 09W will intensify to a tropical storm during the next 24 hours.  It is likely to strengthen to a typhoon by the end of the week.

Tropical Depression 09W will move around the southern part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer the tropical depression toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Tropical Depression 09W will pass near Ujelang in 12 hours.  Tropical Depression 09W could approach the Marianas in four days.  It is likely to be a typhoon when it approaches the Marianas.

Tropical Depression 09W will bring gusty winds and heavy rain to Ujelang.  Heavy rain could cause flash floods.

Tropical Storm Mekkhala Passes West of Okinawa

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The center of Tropical Storm Mekkhala passed west of Okinawa on Thursday.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Mekkhala was located at latitude 27.9°N and longitude 127.5°E which put the center about 80 miles (130 km) northwest of Okinawa.  Mekkhala was moving toward the north-northeast at 9 m.p.h. (15 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 983 mb.

Tropical Storm Mekkhala continued to weaken as it passed west of Okinawa on Thursday.  Mekkhala moved under the southern part of an upper level trough that was over South Korea,  The upper level trough produced westerly winds that blew toward the top of Mekkhala’s circulation.  Those winds caused strong vertical wind shear.  The strong vertical wind shear blew the tops off of most of the thunderstorms in Tropical Storm Mekkhala.  Bands revolving around the center of Mekkhala’s circulation consisted primarily of showers and lower clouds.

The distribution of wind speeds in Tropical Storm Mekkhala became more asymmetrical on Thursday.  Winds to tropical storm force extended out 140 miles (225 km) in the eastern side of Mekkhala’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) in the western side of Tropical Storm Mekkhala.

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 26°C.  However, the upper level trough over South Korea will continue to cause strong vertical wind shear.  Tropical Storm Mekkhala could weaken to a tropical depression during the next 24 hours.

Tropical Storm Mekkhala will move around the northwestern part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mekkhala toward the east-northeast during the next 24 hours.  On its anticipated track, Tropical Storm Mekkhala will be near Tokyo in 36 hours.

Tropical Storm Mekkhala could bring gusty winds to the southern coast of Honshu including Tokyo during the next 48 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Higos strengthened south of Japan.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Higos was located at latitude 26.3°N and longitude 133.9°E which put the center about 155 miles (250 km) east-southeast of Minamidaitojima, Japan.  Higos was moving toward the north at 30 m.p.h. (48 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 986 mb.

Tropical Storm Mekkhala Nears Southern Ryukyu Islands

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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

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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 Higos Forms Near the Marianas

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Tropical Storm Higos formed over the Western North Pacific Ocean near the Marianas on Monday evening.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Higos was located at latitude 14.8°N and longitude 145.1°E which put the center about 20 miles (30 km) south of Tinian.  Higos was moving toward the west-northwest at 11 m.p.h. (17 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 1005 mb.

Tropical Storm Warnings are in effect for Tinian and Saipan.

A low pressure system near the Marianas strengthened on Monday evening and the Japan Meteorological Agency designated the system as Tropical Storm Higos.

A weather station at the Saipan International Airport (PGSN) reported a sustained wind speed of 38 m.p.h. (61 km/h) and a wind gust of 60 m.p.h. (96 km/h).

The distribution of thunderstorms in Tropical Storm Higos was asymmetrical.  Thunderstorms were occurring in bands in the northern and western parts of Higos’ circulation.  Bands in the southern and eastern parts of Tropical Storm Higos consisted primarily of showers and lower clouds.  Storms near the center of HIgos began to generate upper level divergence that pumped mass away to the west of the tropical storm.

The distribution of wind speeds in Tropical Storm Higos was also asymmetrical.  Winds to tropical storm force extended out 80 miles (130 km) in the northern half of Higos’ circulation.  The winds in the southern half of Tropical Storm Higos were blowing at less than tropical storm force.

Tropical Storm Higos will move through an environment that will be somewhat favorable for intensification.  Higos 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 south of Japan. The upper level ridge will produce easterly winds that will blow toward the top of Higos’ 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 Higos could intensify during the next 24 hours.

Tropical Storm Higos will move around the western end of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer HIgos toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Higos will move gradually away from the Marianas.

Tropical Storm Higos will bring gusty winds and locally heavy rain to Tinian and Saipan.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Typhoon Mekkhala started to move toward the southern Ryukyu Islands.  At 11:00 p.m. EDT on Monday the center of Typhoon Mekkhala was located at latitude 19.2°N and longitude 125.1°E which put the center about 370 miles (595 km) south of Miyakojima, Japan.  Mekkhala was moving toward the west-northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 943 mb.

Typhoon Mekkhala Strengthens to Equivalent of Cat. 4 Hurricane

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Typhoon Mekkhala strengthened to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Monday as it moved over the Western North Pacific Ocean east of northern Luzon.  At 11:00 a.m. EDT on Monday the center of Typhoon Mekkhala was located at latitude 18.3°N and longitude 125.9°E which put the center about 305 miles (490 km) east of Aparri, Philippines.  Mekkhala was moving toward the west-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 937 mb.

Typhoon Mekkhala strengthened to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Monday.  A circular eye with a diameter of 25 miles (40 km) was present at the center of Typhoon Mekkhala.  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 Mekkhala’s circulation.  Storms near the center of Mekkhala generated strong upper level divergence that pumped mass away from the typhoon.  The removal of large amounts of mass caused the surface pressure to decrease.

The distribution of winds speeds in Typhoon Mekkhala was fairly symmetrical.  Winds to typhoon force extended out 25 miles (40 km) from the center of Mekkhala’s circulation.  Winds to tropical storm force extended out 140 miles (225 km) from the center of Typhoon Mekkhala.

The Hurricane Intensity Index (HII) for Typhoon Mekkhala is 29.9. The Hurricane Size Index (HSI) is 10.0 and the Hurricane Wind Intensity Size Index (HWISI) is 39.9.  Typhoon Mekkhala is similar in intensity to Hurricane Charley when Charley hit Southwest Florida in 2004.  Mekkhala is a little larger than Charley was.

Typhoon Mekkhala will move through an environment favorable for intensification during the next 24 hours.  Mekkhala will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is southwest of Japan. The upper level winds are weak in the middle of the ridge and there will be little vertical wind shear.  Typhoon Mekhala could intensify during the next 24 hours unless the inner end of a rainband wraps around the existing eye and eyewall.  If concentric eyewalls form, then an eyewall replacement cycle would cause Mekkhala to weaken.  Typhoon Mekkhala could strengthen to the equivalent of a Category 5 hurricane, if there is no eyewall replacement cycle.

Typhoon Mekkhala will move around the southwestern part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mekkhala toward the northwest during the next 24 hours.  On its anticipated track, Typhoon Mekkhala will move toward the southern Ryukyu Islands.  Mekkhala could approach the southern Ryukyu Islands in 60 hours.

Typhoon Mekkhala Rapidly Intensifies to Equivalent of Major Hurricane

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Typhoon Mekkhala rapidly intensified to the equivalent of a major hurricane on Sunday.  At 11:00 p.m. EDT on Sunday the center of Typhoon Mekkhala was located at latitude 17.7°N and longitude 127.4°E which put the center about 415 miles (670 km) east-southeast of Aparri, Philippines.  Mekkhala was moving toward the west at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 961 mb.

Typhoon Mekkhala rapidly intensified to the equivalent of a major hurricane.  The inner end of a rainband wrapped around the center of Mekkhala’s circulation.  A circular eye with a diameter of 25 miles (40 km) formed at the center of Typhoon Mekkhala.  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 Mekkhala’s circulation.  Storms near the center of Mekkhala generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The distribution of winds speeds in Typhoon Mekkhala became more symmetrical on Sunday.  Winds to typhoon force extended out 25 miles (40 km) from the center of Mekkhala’s circulation.  Winds to tropical storm force extended out 140 miles (225 km) from the center of Typhoon Mekkhala.

The Hurricane Intensity Index (HII) for Typhoon Mekkhala is 20.6.  The Hurricane Size Index (HSI) is 10.0 and the Hurricane Wind Intensity Size Index (HWISI) is 30.6.  Typhoon Mekkhala is similar in intensity to Hurricane Delta when Delta hit Southwest Louisiana in 2020.  Mekkhala is a little smaller than Delta was.

Typhoon Mekkhala will move through an environment favorable for intensification during the next 24 hours.  Mekkhala will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge that is southwest of Japan.  The upper level winds are weak in the middle of the ridge and there will be little vertical wind shear.  Typhoon Mekhala will intensify during the next 24 hours.  Mekkhala could continue to intensify rapidly during the next few hours.

Typhoon Mekkhala will move around the southwestern part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mekkhala toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Mekkhala will move closer to northern Luzon. Mekkhala is likely to move more slowly in a couple of days when it reaches the western end of the high pressure system.  Typhoon Mekkhala is also likely to move toward the north when it reaches the western end of the high pressure system

Mekkhala Strengthens to a Typhoon

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Former Tropical Storm Mekkhala strengthened to a typhoon over the Western North Pacific Ocean east of Luzon on Saturday night.  At 5:00 a.m. EDT on Sunday the center of Typhoon Mekkhala was located at latitude 16.4°N and longitude 131.3°E which put the center about 710 miles (1145 km) east-southeast of Aparri, Philippines.  Mekkhala was moving toward the 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 988 mb.

Former Tropical Storm Mekkhala strengthened to a typhoon on Saturday night.  The inner end of a rainband wrapped around the southern side of Mekkhala’s circulation.  Other bands of showers and thunderstorms were revolving around the center of Typhoon Mekkhala.  Storms near the center of Mekkhala generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the northern side of Typhoon Mekkhala.  Winds to typhoon force extended out 25 miles (40 km) in the northern half of Mekkhala’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) in the northern side of Typhoon Mekkhala.  Winds to tropical storm force only extended out 40 miles (65 km) in the southern half of Mekkhala’s circulation.

Typhoon Mekkhala will move through an environment favorable for intensification during the next 24 hours.  Mekkhala will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the southern part of an upper level ridge that is southwest of Japan. The upper level ridge will produce easterly winds that will blow toward the top of Mekkhala’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Typhoon Mekhala will intensify during the next 24 hours.  Mekkhala could strengthen to the equivalent of a major hurricane during the next few days.

Typhoon Mekkhala will move around the southwestern part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mekkhala toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Mekkhala will move toward northern Luzon.  Mekkhala is likely to move more slowly in a couple of days when it reaches the western end of the high pressure system.