Monthly Archives: November 2019

Typhoon Kammuri Churns West Over Philippine Sea

Typhoon Kammuri churned westward over the Philippine Sea on Friday night.  At 10:00 p.m. EST on Friday the center of Typhoon Kammuri was located at latitude 13.9°N and longitude 135.7°E which put it about 1015 miles (1640 km) east of Manila, Philippines.  Kammuri was moving toward the west at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 110 m.p.h. (175 km/h).  The minimum surface pressure was 970 mb.

Typhoon Kammuri exhibited few changes on Friday.  The eye and eyewall were still not fully formed.  The tops of strong thunderstorms near the eye were obscuring the center of circulation on conventional satellite images.  Many of the stronger thunderstorms were occurring in bands in the western half of the circulation.  Bands in the eastern half of Kammuri consisted of showers and lower clouds.  Storms near the center of circulation were generating strong upper level divergence which was pumping mass away from the typhoon.

The circulation around Typhoon Kammuri did increase in size on Friday.  Winds to typhoon force extended out 50 miles (80 km).  Winds to tropical storm force extended out 230 miles (370 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Kammuri was 13.9.  The Hurricane Size Index (HSI) was 18.8 and the Hurricane Wind Intensity Size Index (HWISI) was 32.7.

Typhoon Kammuri will move through an environment favorable for intensification during the next two to three days.  Kammuri will move over water where the Sea Surface Temperature is near 29°C.  It will move through an environment where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Kammuri will intensify and it could strengthen into the equivalent of a major hurricane.  A period of more rapid intensification could occur once an eye and eyewall are fully formed.

Typhoon Kammuri will move south of a high pressure system over the Western North Pacific Ocean.  The high will steer Kammuri toward the west.  On its anticipated track Typhoon Kammuri could approach Luzon in about 72 hours.  Kammuri could be the equivalent of a major hurricane when it approaches Luzon.

Typhoon Kammuri Turns Back Toward the Philippines

After jogging toward the north on Thursday, Typhoon Kammuri turned back toward the Philippines on Thursday night.  At 10:00 p.m. EST on Thursday the center of Typhoon Kammuri was located at latitude 14.1°N and longitude 138.0°E which put it about 1150 miles (1850 km) east of Manila, Philippines.  Kammuri was moving toward the west-northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 110 m.p.h. (175 km/h).  The minimum surface pressure was 970 mb.

Typhoon Kammuri strengthened gradually on Thursday.  The eye that was forming on Wednesday was not yet apparent on conventional infrared or visible satellite images.  Microwave satellite images still indicated that an eye was developing at the center of circulation.  So, high clouds from thunderstorms around the center of Kammuri must have been obscuring the eye on other satellite images.  The upper part of the circulation may have been tilted toward the north by southerly winds blowing around the western end of an upper level ridge.  Winds to typhoon force extended out 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extended out 145 miles (230 km) from the center.

Typhoon Kammuri will move through an environment favorable for intensification during the next several days.  Kammuri will move over water in the Philippine Sea where the Sea Surface Temperature is 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 Kammuri will continue to intensify and it could strengthen into the equivalent of a major hurricane during the next 24 to 48 hours.  There could be a period of rapid intensification after the eye and eyewall are fully developed.

Typhoon Kammuri will move south of a high pressure system that extends from eastern Asia over the Western North Pacific Ocean.  The high will steer Kammuri toward the west during the next few days.  On its anticipated track Typhoon Kammuri could approach Luzon in about four days.  Kammuri could be the equivalent of a major hurricane when it reaches Luzon.

Typhoon Kammuri Strengthens North of Yap

Typhoon Kammuri strengthened north of Yap on Wednesday night.  At 10:00 p.m. EST on Wednesday the center of Typhoon Kammuri was located at latitude 12.0°N and longitude 138.8°E which put it about 160 miles (260 km) north-northeast of Yap.  Kammuri was moving toward the west-northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 976 mb.

Typhoon Kammuri continued to get stronger on Wednesday night.  The inner end of a rainband wrapped around the center of circulation and an eye was clearing out at the center of Kammuri.  Bands of showers and thunderstorms were revolving around the center of circulation.  The strongest rainbands were in the western half of Typhoon Kammuri.  Storms near the center were generating upper level divergence which was pumping mass away from the typhoon.  Winds to typhoon force extended out 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center.

Typhoon Kammuri will move through an environment favorable for intensification during the next few days.  Kammuri will move over where the Sea Surface Temperature is near 29°C.  It will move through an environment where the upper level winds will be weak and there will be little vertical wind shear.  Typhoon Kammuri will continue to intensify and it could strengthen into the equivalent of a major hurricane within 24 to 36 hours.  A period of rapid intensification could occur once an eye and eyewall are fully formed.

Typhoon Kammuri will move near the western end of a subtropical high pressure sytem over the Western North Pacific Ocean during the next 24 to 36 hours.  Kammuri could move more toward the northwest during that time period.  A second surface high pressure system will move eastward from Asia.  The second high will eventually block Typhoon Kammuri from moving northward and that high pressure system will steer Kammuri toward the west.  On its anticipated track Typhoon Kammuri could approach the Philippines in five or six days.  Kammuri could be a very strong typhoon when it approaches the Philippines.

Tropical Storm Kammuri Passes South of Guam

Tropical Storm Kammuri passed south of Guam on Tuesday.  At 10:00 p.m. EST on Tuesday the center of Tropical Storm Kammuri was located at latitude 11.8°N and longitude 141.8°E which put it about 225 miles (365 km) southwest of Guam.  Kammuri was moving toward the west at 14 m.p.h. (22 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 985 mb.  The Tropical Storm Warnings for Guam, Rota, Saipan and Tinian were discontinued.

The circulation around Tropical Storm Kammuri exhibited greater organization on Tuesday.  Rainbands around the center of circulation were more circular.  Storms near the center were generating upper level divergence which was pumping mass away to the north and west of the tropical storm.  There were also more thunderstorms in bands north and west of the center of Kammuri.  Bands southeast of the center consisted primarily of showers and lower clouds.  The wind field around Tropical Storm Kammuri was also asymmetrical.  Winds to tropical storm force extended out farther in the northern half of the circulation.  Winds to tropical storm force extended out 240 miles (340 km) to the northeast of the center of Kammuri.  In contrast, tropical storm force winds only extended out 75 miles (120 km) to the southeast of the center of circulation.

Tropical Storm Kammuri will move through an environment favorable for intensification during the next few days.  Kammuri will move over water where the Sea Surface Temperature is near 29°C.  It will move under the western end of an upper level ridge.  The ridge will produce easterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear.  The shear will slow the rate of intensification, but it will not be strong enough to prevent Tropical Storm Kammuri from getting stronger.  Kammuri is likely to intensify into a typhoon during the next 24 hours and it could strengthen into the equivalent of a major hurricane later this week.

Tropical Storm Kammuri will move around the western end of a subtropical high pressure system over the Western Pacific Ocean during the next 48 to 72 hours.  The ridge will steer Kammuri toward the northwest.  A second high pressure system will move eastward from Asia in about three days.  The second high will block Tropical Storm Kammuri from moving any farther toward the north and the high will steer Kammuri toward the west during the weekend.  On its anticipated track Tropical Storm Kammuri will gradually move closer to the Philippines.

Elsewhere, over the South Pacific Ocean near Vanuatu vertical wind shear weakened Tropical Cyclone Rita.  At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Rita was located at latitude 15.3°S and longitude 169.0°E which put it about 180 miles (290 km) north of Port Vila, Vanuatu.  Rita was moving toward the south 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 1000 mb.

Tropical Storm Kammuri Forms, Warnings Issued for Marianas

Tropical Storm Kammuri formed on Monday and warnings were issued for the Marianas.  At 10:00 p.m. EST on Monday the center of Tropical Storm Kammuri was located at latitude 10.2°N and longitude 149.0°E which put it about 415 miles (665 km) southeast of Guam.  Kammuri was moving toward the west-northwest at 16 m.p.h. (26 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.

Tropical Storm Warnings were in effect for Guam, Rota, Tinian and Saipan.

More thunderstorms formed near the center of a large low pressure system southeast of Guam on Monday and the Japan Meteorological Agency designated the system as Tropical Storm Kammuri.  The circulation around Kammuri was still organizing on Monday night.  Multiple bands of showers and thunderstorms were forming and the bands were starting to revolve around the center of circulation.  Storms near the center began to generate upper level divergence which was pumping mass away from the tropical storm in all directions.

Tropical Storm Kammuri will move through an environment favorable for intensification during the next few days.  Kammuri will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Kammuri will continue to intensify and it could strengthen into a typhoon within 36 hours.  Kammuri could eventually intensify into the equivalent of a major hurricane.

Tropical Storm Kammuri will move south of a subtropical high pressure system over the Western North Pacific Ocean during the next two days.  The high will steer Kammuri toward the west-northwest.  On its anticipated track the center of Tropical Storm Kammuri will pass south of Guam in about 18 to 24 hours.  Kammuri could bring gusty winds and locally heavy rain.  An upper level trough will approach Tropical Storm Kammuri from the northwest in about 48 hours.  The trough will weaken the upper level ridge and the steering currents will weaken.  Kammuri could meander after the steering currents weaken.

Elsewhere, over the South Pacific Ocean Tropical Cyclone Rita was weakening northeast of Vanuatu.  At 10:00 p.m. EST on Monday the center of Tropical Cyclone Rita was located at latitude 14.3°S and longitude 170.0°E which put it about 265 miles (430 km) north-northeast of Port Vila, Vanuatu.  Rita was moving toward the south-southwest 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 990 mb.

Tropical Cyclone Rita Develops North of Vanuatu

Tropical Cyclone Rita developed over the South Pacific Ocean north of Vanuatu on Sunday.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Rita was located at latitude 11.5°S and longitude 169.4°E which put it about 455 miles (730 km) north of Port Vila, Vanuatu.  Rita was moving toward the south-southeast at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 987 mb.

A center of circulation in an area of low pressure north of Vanuatu exhibited greater organization on Sunday and the system was designated Tropical Cyclone Rita.  Rita had a distinct low level center of circulation.  A band of showers and thunderstorms wrapped around the western and northern sides of the center.  Other rainbands were revolving around the center of circulation.  Storms near the center were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to tropical storm force extended out 120 miles (195 km) from the center of circulation.

Tropical Cyclone Rita will move through an environment relatively favorable for intensification during the next 24 hours.  Rita will move over water where the Sea Surface Temperature is near 28°C.  It will move under the western end of an upper level ridge over the South Pacific Ocean.  The ridge will produce northerly winds which will blow toward the top of the tropical cyclone.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but the shear will not be strong enough to prevent Tropical Cyclone Rita from getting stronger.  Rita could strengthen into the equivalent of a hurricane/typhoon during the next 24 hours.

The ridge over the South Pacific Ocean will steer Tropical Cyclone Rita toward the south during several days.  On its anticipated track the center to Rita could approach Vanuatu in 48 to 72 hours.

Tropical Storm Sebastien Speeds East

Tropical Storm Sebastien sped eastward across the Atlantic Ocean on Friday.  At. 4:00 p.m. EST on Friday the center of Tropical Storm Sebastien was located at latitude 26.2°N and longitude 53.7°W which put it about 815 miles (1315 km) northeast of the Leeward Islands.  Sebastien was moving toward the east-northeast at 16 m.p.h. (26 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 999 mb.

An upper level trough over the western Atlantic Ocean was producing strong southwesterly winds which were blowing toward the top of Tropical Storm Sebastien.  Those winds were producing moderate vertical wind shear.  The shear was contributing to an asymmetrical distribution of thunderstorms around Sebastien.  Stronger thunderstorms were occurring in bands north and east of the center of circulation.  Bands south and west of the center consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 200 miles (325 km) from the center of circulation.

Tropical Storm Sebastien will move through an environment that could permit it to maintain its intensity for another day or so.  Sebastien will move over water where the Sea Surface Temperature is near 25.5°C.  The upper level trough over the western Atlantic will continue to cause moderate vertical wind shear, which will inhibit intensification.  Sebastien will move over cooler water during the weekend and it should start to weaken at that time.

The upper level trough will steer Tropical Storm Sebastien toward the northeast during the weekend.  On its anticipated track Sebastien will move toward the Azores.  Sebastien is forecast to merge with a cold front before it reaches the Azores.

Tropical Storm Fung-wong Nears Southern Ryukyu Islands

Tropical Storm Fung-wong neared the southern Ryukyu Islands on Thursday night.  At 10:00 p.m. EDT on Thursday the center of Tropical Storm Fung-wong was located at latitude 23.3°N and longitude 124.9°E which put it about 110 miles (175 km) south-southwest of Harari, Japan.  Fung-wong was moving toward the north-northeast at13 m.p.h. (20 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 989 mb.

Tropical Storm Fung-wong was weakening gradually as it neared the southern Ryukyu Islands.  An upper level trough over east Asia was producing southwesterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear.  There was still a well defined low level center of circulation.  A broken ring of thunderstorms surrounded the center and the strongest winds were occurring near the center of Fung-wong.  Most of the stronger thunderstorms were occurring in bands north and east of the center of circulation.  Bands in the southern and western parts of the tropical storm consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 120 miles (195 km) from the center of circulation.

A high pressure system over the Western North Pacific Ocean and the trough over east Asia will interact to steer Tropical Storm Fung-wong toward the north-northeast during the next 24 to 36 hours.  On its anticipated track Fung-wong will move over the southern Ryukyu Islands during the next 24 hours.  The center of the tropical storm could pass close to Miyako Jima in about 12 hours.  Tropical Storm Fung-wong will continue to weaken gradually because of the moderate vertical wind shear.  Fung-wong will bring gusty winds and locally heavy rain to some of the southern Ryukyu Islands.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Kalmaegi was moving across the South China Sea toward Vietnam.  At 10:00 p.m. EST on Thursday the center of Tropical Depression Kalmaegi was located at latitude 11.5°N and longitude 114.5°E which put it about 550 miles (890 km) east of Ho Chi Minh City, Vietnam.  Kalmaegi was moving toward the west-southwest 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 1004 mb.  Tropical Depression Kalmaegi could drop locally heavy rain over parts of southern Vietnam during the weekend.

Tropical Storm Kalmaegi Brings Wind and Rain to Northern Luzon

Tropical Storm Kalmaegi brought wind and rain to northern Luzon on Tuesday night.  At 10:00 p.m. EST on Tuesday the center Tropical Storm Kalmaegi was located at latitude 17.0°N and longitude 121.2°W which put it about 70 miles (110 km) northeast of Baguio, Philippines.  Kalmaegi was moving toward the south-southwest at 15 m.p.h. (24 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 987 mb.

Former Typhoon Kalmaegi weakened to a tropical storm before it made landfall on the north coast of Luzon near Aparri.  Kalmaegi was under the western end of an upper level ridge.  The ridge produced strong southerly winds which blew toward the top of the circulation.  Those winds caused moderate vertical wind shear which weakened thunderstorms in the southern half of the circulation.  Drier air from Asia was pulled into the western part of the tropical storm.  The stronger thunderstorms were occurring northeast of the center of circulation.  Winds to tropical storm force extended out 100 miles (160 km) from the center in most parts of Tropical Storm Kalmaegi.  A high pressure system over Asia was contributing to a bigger pressure gradient in the northwestern quadrant of Kalmaegi and winds to tropical storm force extended out 200 miles (320 km) in that area.

Tropical Storm Kalmaegi was dropping locally heavy rain over parts of northern Luzon.  The heavy rain was creating the potential for flash floods.  Kalmaegi will be steered toward the southwest by the high pressure system over Asia. On its anticipated track the center of Tropical Storm Kalmaegi will pass near Baguio.  Kalmaegi will continue to weaken as it moves over northern Luzon.  It will move over the South China Sea northwest of Manila.  Tropical Storm Kalmaegi will continue to drop heavy rain over parts of Luzon and the flash flood threat will continue for several more days.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Fung-wong developed east of Luzon on Tuesday night.  At 10:00 p.m. EST the center of Tropical Storm Fung-wong was located at latitude 16.3°N and longitude 127.8°E which put it about 425 miles (685 km) east-southeast of Aparri, Philippines.  Fung-wong 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 1000 mb.  Tropical Storm Fung-wong is forecast to strengthen during the next 36 hours while it moves toward the Luzon Strait.

Tropical Storm Sebastien Forms Northeast of the Leeward Islands

Tropical Storm Sebastien formed northeast of the Leeward Islands on Tuesday morning.  At 10:00 a.m. EST on Tuesday the center of Tropical Storm Sebastien was located at latitude 20.1°N and longitude 58.7°W which put it about 275 miles (445 km) northeast of the Leeward Islands.  Sebastien was moving toward the north-northwest at 8 m.p.h. (13 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 1008 mb.

More thunderstorms developed closer to the center of a low pressure system northeast of the Leeward Islands on Tuesday morning and the National Hurricane Center designated the system as Tropical Storm Sebastien.  There was a distinct low level center of circulation evident on visible satellite imagery.  However, the distribution of thunderstorms was asymmetrical.  The stronger thunderstorms were occurring in bands in the eastern half of the circulation.  Bands in the western half of the circulation consisted primarily of showers and lower clouds.  Storms near the center were generating upper level divergence which was pumping mass away to the east of the tropical storm.  Winds to tropical storm force were occurring primarily in the northeastern quadrant of Sebastien.  Those winds extended out 100 miles (160 km) from the center of circulation.

Tropical Storm Sebastien will move through an environment marginally favorable for intensification during the next day or two.  Sebastien will move over water where the Sea Surface Temperature is near 28°C.  So, there will be sufficient energy in the upper ocean to support intensification.  An upper level trough near the east coast of the U.S. will produce southwesterly winds which will blow toward the top of the circulation.  Those winds will create moderate vertical wind shear and they are probably contributing to the asymmetrical distributions of thunderstorms.  Tropical Storm Sebastien could strengthen if the shear does not increase.  However, if the upper level winds get stronger, then wind shear will cause Sebastien to weaken.

The upper level trough near the east coast of the U.S. and a subtropical high pressure system over the Atlantic Ocean will interact to steer Tropical Storm Sebastien toward the north during the next 24 to 36 hours.  On its anticipated track Sebastien will move away from the Leeward Islands and it is forecast to stay southeast of Bermuda.