Category Archives: Tropical Cyclones

Information about tropical cyclones

Subtropical Storm Teresa Develops North of Bermuda

Subtropical Storm Teresa developed north of Bermuda on Friday afternoon. At 5:00 p.m. EDT on Friday the center of Subtropical Storm Teresa was located at latitude 34.5°N and longitude 64.5°W which put it about 155 miles (245 km) north of Bermuda. Teresa 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 1008 mb.

A distinct low level of circulation was evident under an upper level low pressure system north of Bermuda and the National Hurricane Center designated the system as Subtropical Storm Teresa. The structure of Subtropical Storm Teresa was complex. There was a distinct low level center of circulation under the western side of the upper level low. A long band of showers and thunderstorms arced around the eastern and northern side of the larger circulation. Winds to tropical storm force extended out 70 miles (110 km) in the northeastern quadrant of Subtropical Storm Teresa. Winds in the other parts of Teresa were blowing at less than tropical storm force.

Subtropical Storm Teresa will move through an environment that is only marginally favorable for intensification during the next 24 hours. Teresa will move over water where the Sea Surface Temperatures are near 27˚C. However, the circulation around the upper level low will cause vertical wind shear over the low level center of Teresa. The wind shear will inhibit intensification. Subtropical Storm Teresa could get a little stronger during the next 24 hours. Teresa is forecast to be absorbed by a larger extratropical cyclone by the end of the weekend.

An upper level trough over the eastern U.S. will steer Subtropical Storm Teresa toward the northeast during the weekend. On its anticipated track, Teresa will move farther away from Bermuda. Subtropical Storm Teresa is forecast to be absorbed by an extratropical cyclone south of Nova Scotia on Sunday.

Elsewhere, Hurricane Same strengthened over the tropical Atlantic Ocean. At 5:00 p.m. EDT on Friday the center of Hurricane Sam was located at latitude 12.1°N and longitude 44.8°W which put it about 1290 miles (2075 km) east-southeast of the Northern Leeward Islands. Sam moving toward the west at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 986 mb. Hurricane Sam is forecast to strengthen to a major hurricane during the weekend.

Sam Strengthens to a Hurricane

Former Tropical Storm Sam strengthened to a hurricane over the Tropical Atlantic Ocean early on Friday. At 5:00 a.m. EDT on Friday the center of Hurricane Sam was located at latitude 11.5°N and longitude 42.2°W which put it about 1470 miles (2365 km) east-southeast of the Northern Leeward Islands. Sam moving toward the west at 15 m.p.h. (24 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 993 mb.

Former Tropical Storm Sam strengthened to a hurricane early on Friday. The inner end of a rainband wrapped around the eastern side of the center of Hurricane Sam. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the hurricane in all directions. The circulation around Hurricane Sam was relatively small. Winds to hurricane force extended out 20 miles (30 km) from the center of Sam. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Hurricane Sam will move through an environment very favorable for intensification during the next 48 hours. Sam 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. Hurricane Sam will continue to intensify during the next 48 hours. Sam could intensify rapidly after an inner core with an eye and an eyewall fully form. Hurricane Sam could intensify to a major hurricane during the weekend.

Hurricane Sam will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high will steer Sam toward the west-northwest during the next few days. On its anticipated track Hurricane Sam could approach the Northern Leeward Islands by the middle of next week. Sam could be a major hurricane at that time.

Tropical Storm Sam Strengthens over Eastern Atlantic

Tropical Storm Sam strengthened over the eastern Atlantic Ocean on Thursday morning. At 11:00 a.m. EDT on Thursday the center of Tropical Storm Sam was located at latitude 10.9°N and longitude 38.1°W which put it about 1745 miles (2805 km) east-southeast of the Northern Leeward Islands. Sam moving toward the west at 16 m.p.h. (26 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 1003 mb.

Former Tropical Depression Eighteen strengthened to Tropical Storm Sam on Thursday morning. Tropical Storm Sam was organizing quickly. The inner end of a rainband wrapped around the center of Sam . An eye appeared to be forming at the center of circulation. Bands of showers and thunderstorms were revolving around the center of Tropical Storm Sam. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 45 miles (75 km) from the center of Sam.

Tropical Storm Sam will move through an environment very favorable for intensification during the next 48 hours. Sam will move over water where the Sea Surface Temperatures are near 28˚C. It will move into a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Sam will continue to intensify during the next 36 hours. Sam could strengthen to a hurricane by Friday. Sam could intensify rapidly after an inner core with an eye and an eyewall forms. Sam could intensify to a major hurricane during the weekend.

Tropical Storm Sam will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high will steer Sam toward the west-northwest during the next few days. On its anticipated track Tropical Storm Sam could approach the Northern Leeward Islands next week. Sam could be a major hurricane by that time.

Tropical Storm Mindulle Brings Wind and Rain to Marianas, Dianmu Hits Vietnam

Tropical Storm Mindulle brought wind and rain to the Marianas on Thursday and Tropical Storm Dianmu hit Vietnam. At 11:00 a.m. EDT on Thursday the center of Tropical Storm Mindulle was located at latitude 14.1°N and longitude 142.3°E which put it about 175 miles (280 km) west-northwest of Guam. Mindulle moving toward the west-northwest at 23 m.p.h. (37 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 997 mb.

Tropical Storm Mindulle brought wind and rain to the Marianas including Guam on Thursday. Tropical Storm Warnings were in effect for Guam, Rota, Tinian and Saipan. Mindulle was intensifying as it moved across the Marianas. More thunderstorms developed about the center of circulation. Bands of showers and thunderstorms were revolving the center of Tropical Storm Mindulle. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. The strongest winds were occurring in the northeastern part of Mindulle. Winds to tropical storm force extended out 150 miles (240 km) in the northeastern quadrant to Mindulle.

Tropical Storm Mindulle will move through an environment favorable for intensification during the next few days. Mindulle will move over water where the Sea Surface Temperatures are near 30˚C. It will move into a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Mindulle will continue to intensify during the next 36 hours. Mindulle could strengthen to a typhoon in 24 hours. Mindulle could intensify more rapidly after an inner core becomes more well developed. It could intensify to the equivalent of a major hurricane during the weekend.

Tropical Storm Mindulle will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean during the next several days. The high will steer Mindulle toward the northwest during the next 48 hours. On its anticipated track Tropical Storm Mindulle will move quickly away from the Marianas. Mindulle could approach the Ryukyu Islands in a few days.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Dianmu bought wind and rain to central Vietnam. At 11:00 a.m. EDT on Thursday the center of Tropical Storm Dianmu was located at latitude 15.4°N and longitude 108.3°E which put it about 15 miles (25 km) southeast of Tam Ky, Vietnam. Dianmu was moving toward the northwest at 17 m.p.h. (28 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 Dianmu will weaken as it moves inlands over Southeast Asia. Dianmu will bring gusty winds and locally heavy rain to central Vietnam, southern Laos and northern Cambodia. Heavy rain could cause flash floods in some locations.

Tropical Depression 20W Forms Southeast of Guam

Tropical Depression Twenty-W formed southeast of Guam on Wednesday. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Twenty-W was located at latitude 11.5°N and longitude 148.1°E which put it about 305 miles (490 km) east-southeast of Guam. The tropical depression moving toward the west-northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). T he minimum surface pressure was 1005 mb.

Tropical Depression Twenty-W developed over the Western North Pacific Ocean southeast of Guam on Wednesday. The circulation around the tropical depression was organizing quickly. Thunderstorms formed near the center of the tropical depression. Other thunderstorms developed in bands revolving around the center of circulation. Storms near the center began to generate upper level divergence that pumped mass away from the depression.

Tropical Depression Twenty-W will move through an environment favorable for intensification during the next few days. The tropical depression will move over water where the Sea Surface Temperatures are near 30˚C. It will move into a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Depression Twenty-W could strengthen to a tropical storm during the next 12 hours. It could intensify more rapidly after an inner core becomes more well developed. It could intensify to a typhoon within 36 hours.

Tropical Depression Twenty-W will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean during the next several days. The high will steer the tropical depression toward the northwest during the next 36 hours. On its anticipated track the tropical depression could reach the Marianas in less than 24 hours. Tropical Depression Twenty-W could intensify to a tropical storm before it reaches the Marianas. It will bring gusty winds and locally heavy rain to the Marianas including Guam.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Twentyone-W formed over the South China Sea east of Vietnam. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Twentyone-W was located at latitude 12.9°N and longitude 112.8°E which put it about 400 miles (605 km) east-southeast of Da Nang, Vietnam. The tropical depression moving toward the west-northwest at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). T he minimum surface pressure was 1005 mb. Tropical Depression Twentyone-W is forecast to move toward the west-northwest and to strengthen to a tropical storm. It could reach the coast of Vietnam south of Da Nang in about 24 hours.

Tropical Storm Peter Passes Northeast of Leeward Islands

Tropical Storm Peter passed northeast of the Leeward Islands on Monday. At 11:00 a.m. EDT on Monday the center of Tropical Storm Peter was located at latitude 19.5°N and longitude 60.9°W which put it about 170 miles (275 km) northeast of the Leeward Islands. Peter was moving toward the west-northwest at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 50 m.p.h. (75 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 1007 mb.

An upper level trough north of Puerto Rico and an upper level ridge east of the Leeward Islands were interacting to produce strong southwesterly winds that were blowing across the circulation around Tropical Storm Peter. Those winds were causing strong vertical wind shear. The low level center of circulation was clearly evident on visible satellite images and it was surrounded by showers and lower clouds. Thunderstorms were occurring in bands on the eastern and northern periphery of the circulation around Tropical Storm Peter. Bands in the western and southern parts of Peter consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 125 miles (200 km) in the northeastern quadrant of Peter’s circulation. The winds in the other parts of the circulation were blowing at less than tropical storm force.

Tropical Storm Peter will move through an environment unfavorable for intensification during the next 36 hours. Peter will move over water where the Sea Surface Temperatures are near 29˚C. However, the upper level trough and the upper level ridge will continue to produce strong vertical wind shear. The strong wind shear will inhibit intensification. Tropical Storm Peter could weaken gradually during the next 36 hours.

Tropical Storm Peter will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Peter toward the west-northwest during the next 36 hours. On its anticipated track Tropical Storm Peter will pass north of the Northern Leeward Islands, the Virgin Islands and Puerto Rico.

Elsewhere over the Atlantic Ocean, Tropical Storm Rose moved away from the Cabo Verde Islands. At 11:00 a.m. EDT on Monday the center of Tropical Storm Rose was located at latitude 17.3°N and longitude 33.4°W which put it about 620 miles (1000 km) west-northwest of the Cabo Verde Islands. Rose was moving toward the 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 1007 mb.

Tropical Depression 16 Strengthens to Tropical Storm Peter

Former Tropical Depression Sixteen strengthened to Tropical Storm Peter on Sunday morning. At 9:00 a.m. EDT on Sunday the center of Tropical Storm Peter was located at latitude 17.6°N and longitude 56.0°W which put it about 470 miles (755 km) east of the Northern Leeward Islands. Peter was moving toward the west-northwest at 15 m.p.h. (24 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.

Infrared satellite images and satellite derived scatterometer estimates of surface winds indicated that former Tropical Depression Sixteen had strengthened on Sunday morning and the National Hurricane Center designated the system as Tropical Storm Peter. Early morning visible satellite images revealed that strong vertical wind shear was affecting Tropical Storm Peter. An upper level trough north-northeast of Puerto Rico and an upper level ridge east of the Leeward Islands were interacting to produce strong southwesterly winds that were blowing across Peter’s circulation. The low level center of circulation was clearly visible on those images and it was surrounded by showers and lower clouds. Thunderstorms were occurring in bands on the eastern and northern periphery of the circulation around Tropical Storm Peter. Bands in the western and southern parts of Peter consisted primarily of showers and lower clouds.

Tropical Storm Peter will move through an environment marginally favorable for intensification during the next 24 hours. Peter will move over water where the Sea Surface Temperatures are near 29˚C. However, the upper level trough and the upper level ridge will continue to produce strong vertical wind shear. The strong wind shear will inhibit intensification. Tropical Storm Peter could strengthen a little during the next 24 hours. The upper level winds are forecast to get stronger on Monday. Increased vertical wind shear could cause Peter to weaken back to a tropical depression.

Tropical Storm Peter will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer the depression toward the west-northwest during the next 48 hours. On its anticipated track Tropical Storm Peter could be northeast of the Northern Leeward Islands by Monday morning.

Elsewhere over the Atlantic Ocean, Tropical Depression Seventeen formed southwest of the Cabo Verde Islands. At 5:00 a.m. EDT on Sunday the center of Tropical Depression Seventeen was located at latitude 11.8°N and longitude 28.21°W which put it about 330 miles (530 km) southwest of the Cabo Verde Islands. The tropical depression was moving toward the north-northwest at 14 m.p.h. (22 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 1007 mb. The tropical depression is forecast to move away from the Cabo Verde Islands and to strengthen to a tropical storm.

Tropical Depression 16 Forms East of Northern Leeward Islands

Tropical Depression Sixteen formed east of the Northern Leeward Islands on Saturday night. At 11:00 p.m. EDT on Saturday the center of Tropical Depression Sixteen was located at latitude 16.4°N and longitude 53.1°W which put it about 670 miles (1080 km) east of the Northern Leeward Islands. The tropical depression was moving toward the west-northwest at 15 m.p.h. (24 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 1008 mb.

More thunderstorms developed near the center of a low pressure system east of the Northern Leeward Islands on Saturday night and the National Hurricane Center designated the system as Tropical Depression Sixteen. Thunderstorms were also developing in bands in the eastern and northern parts of the tropical depression. Bands in the southern and western parts of the circulation consisted primarily of showers and lower clouds. Storms near the center of circulation generated upper level divergence that pumped mass away to the north of the tropical depression.

Tropical Depression Sixteen will move through an environment somewhat favorable for intensification during the next 24 hours. The depression will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western part of an upper level ridge. The ridge will produce southerly winds that will blow toward the top of the tropical depression. Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification. Tropical Depression Sixteen is likely to strengthen to a tropical storm on Sunday. The tropical depression will move closer to an upper level trough northeast of Puerto Rico on Monday. The upper level trough will produce strong southwesterly winds that will blow toward the top of the tropical depression. Those winds will cause moderate vertical wind shear, which is likely to weaken the tropical depression.

Tropical Depression Sixteen will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer the depression toward the west-northwest during the next 24 hours. On its anticipated track Tropical Depression Sixteen could be northeast of the Northern Leeward Islands by Monday morning.

Elsewhere over the Atlantic Ocean, Tropical Storm Odette made a transition to an extratropical cyclone south of Nova Scotia. At 5:00 p.m. EDT on Saturday the center of former Tropical Storm Odette was located at latitude 39.1°N and longitude 65.1°W which put it about 385 miles (625 km) south-southwest of Halifax, Nova Scotia. Odette was moving toward the east-northeast at 18 m.p.h. (29 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 1001 mb.

Tropical Storm Odette Forms South of New England

Tropical Storm Odette formed south of New England on Friday afternoon. At 5:00 p.m. EDT on Friday the center of Tropical Storm Odette was located at latitude 36.7°N and longitude 71.8°W which put it about 325 miles (525 km) south-southwest of Nantucket, Massachusetts. Odette was moving toward the northeast at 15 m.p.h. (24 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 1010 mb.

A new circulation center developed on the northern side of a larger low pressure system over the Atlantic Ocean south of New England on Friday afternoon and the National Hurricane Center designated the system as Tropical Storm Odette. The low level center of Odette was surrounded by lower clouds and showers. Thunderstorms were occurring in bands on the northern and eastern periphery of Tropical Storm Odette. Bands in the other parts of Odette’s circulation consisted primarily of showers and lower clouds. An upper level trough over the eastern U.S. was producing southwesterly winds that were blowing across the top of Tropical Storm Odette. Those winds were causing moderate vertical wind shear and the wind shear was contributing to the asymmetrical distribution of thunderstorms. Winds to tropical storm force extended out 115 miles (185 km) on the eastern side of Odette. The winds on the western side of the circulation were blowing at less than tropical storm force.

Tropical Storm Odette will move through an environment that is somewhat favorable for intensification during the next 36 hours. Odette will move over water in the Gulf Stream where the Sea Surface Temperatures are near 28˚C. The upper level trough over the eastern U.S. will continue to cause vertical wind shear, but the shear could decrease on Saturday. Tropical Storm Odette could strengthen during the next 24 hours. Odette will move over cooler water later in the weekend when it moves north of the Gulf Stream. Tropical Storm Odette will make a transition to an extratropical cyclone when it moves over cooler water. Odette could strengthen during the transition to an extratropical cyclone.

The upper level trough over the eastern U.S. will steer Tropical Storm Odette toward the northeast during the next 48 hours. On its anticipated track Tropical Storm Odette will pass southeast of Cape Cod. Odette could approach southeastern Newfoundland by late in the weekend.

Tropical Storm Chanthu Brings Gusty Winds and Rain to Japan

Tropical Storm Chanthu brought gusty winds and rain to parts of Japan on Friday. At 6:00 a.m. EDT on Friday the center of Tropical Storm Chanthu was located at latitude 33.7°N and longitude 130.6°E which put it about 10 miles (15 km) east of Fukuoka, Japan. Chanthu was moving toward the east-northeast at 17 m.p.h. (28 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 990 mb.

Tropical Storm Chanthu brought gusty winds to northern Kyushu and western Honshu on Friday. Winds to tropical storm force extended out 115 miles (185 km) from the center of Chanthu. The strongest winds were occurring in the parts of Chanthu’s circulation that were over water and in the mountains of western Japan. The heaviest rain was falling on the eastern side of Tropical Storm Chanthu.

Tropical Storm Chanthu will be steered quickly toward the east-northeast by the westerly winds in the middle latitudes. Tropical Storm Chanthu will move across Honshu during the next two days. The center of Tropical Storm Chanthu could be near Kyoto in 24 hours and near Tokyo in 36 hours. The upper level westerly winds will cause moderate vertical wind shear. The wind shear and movement across land will cause Chanthu to weaken gradually during the next 48 hours.