Tag Archives: Leeward Islands

Hurricane Tammy Moves North of the Leeward Islands

Hurricane Tammy moved north of the Leeward Islands on Sunday. At 11:00 p.m. EDT on Sunday the center of Hurricane Tammy was located at latitude 20.8°N and longitude 64.0°W which put it about 190 miles (305 km) north-northwest of Anguilla. Tammy was moving toward the northwest 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 100 m.p.h. (160 km/h). The minimum surface pressure was 993 mb.

Hurricane Tammy maintained its intensity on Sunday as it moved north of the Leeward Islands, but Tammy was looking a little weaker on Sunday evening. An upper level trough near the east coast of the U.S. was producing strong southwesterly winds that were blowing toward the top of Tammy’s circulation. Those winds were causing strong vertical wind shear. In addition, some drier air appeared to be entering the southwestern part of Hurricane Tammy.

The effects of the strong wind shear and the drier air caused the distribution of thunderstorms in Hurricane Tammy to become asymmetrical again. Many of the thunderstorms were occurring in bands in the northern and eastern parts of Tammy’s circulation. Bands in the western and southern parts of the circulation consisted primarily of showers and lower clouds. Winds to hurricane force extended out 25 miles (40 km) from the center of Hurricane Tammy. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation.

Hurricane Tammy will move through an environment that will be unfavorable for intensification during the next 24 hours. Tammy will move over water where the Sea Surface Temperatures are near 29°C. However, the upper level trough near the east coast of the U.S. will continue to cause strong vertical wind shear. The strong wind shear will inhibit intensification and Hurricane Tammy could weaken on Monday.

Hurricane Tammy will move around the western end of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Tammy toward the north during the next 24 hours. On its anticipated track, Hurricane Tammy will move farther north of the Leeward Islands on Monday.

Hurricane Tammy Passes Over Barbuda

Hurricane Tammy passed over Barbuda on Saturday night. At 11:00 p.m. EDT on Saturday the center of Hurricane Tammy was located at latitude 17.8°N and longitude 61.9°W which put it about 15 miles (25 km) north-northwest of Barbuda. Tammy was moving toward the north-northwest at 10 m.p.h. (16 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 992 mb.

Hurricane Warnings were in effect for Anguilla, Barbuda, St. Maarten, St, Martin, and St. Barthelemy. Tropical Storm Warnings were in effect for Saba and St. Eustatius.

The center of Hurricane Tammy passed directly over Barbuda on Saturday evening. Tammy produced strong gusty winds and heavy rain in Barbuda. Heavy rain was likely to cause flash floods in some locations.

Hurricane Tammy showed signs of weakening a little on Saturday night. Breaks appeared in the ring of thunderstorms around the center Tammy’s circulation. The distribution of thunderstorms became more asymmetrical. Many of the thunderstorms were occurring in bands in the eastern and northern parts of Hurricane Tammy. Bands in the southern and western parts of Tammy’s circulation consisted primarily of showers and lower clouds. Storms near the center of Tammy’s circulation generated upper level divergence that pumped mass away from the hurricane.

Winds to hurricane force extended out 25 miles (40 km) from the center of Hurricane Tammy. Winds to tropical storm force extended out 125 miles (200 km) from the center of circulation. The Hurricane Intensity Index (HII) was 12.7. The Hurricane Size Index (HSI) was 8.3 and the Hurricane Wind Intensity Size Index (HWISI) was 21.0. Hurricane Tammy was capable of causing localized minor damage.

Hurricane Tammy will move through an environment somewhat favorable for intensification during the next 24 hours. Tammy will move over water where the Sea Surface Temperatures are near 29°C. It will move under the northeastern part of an upper level low over the Eastern Caribbean Sea. The upper level low will produce southwesterly winds that will blow toward the top of Tammy’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will inhibit intensification. The wind shear could be strong enough to cause Hurricane Tammy to weaken during the next 24 hours.

Hurricane Tammy will move around the western end of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Tammy toward the north during the next 24 hours. On its anticipated track, the center of Hurricane Tammy will move north of the Leeward Islands on Sunday.

Hurricane Tammy will continue to produce strong winds and heavy rain in Barbuda during the next few hours. The weather conditions will start to improve in Barbuda when Tammy moves north of the Leeward Islands on Sunday. Hurricane Tammy could also bring gusty winds to Anguilla, St. Maarten, St. Martin and St. Barthelemy on Sunday.

Tropical Storm Lee Forms East of the Lesser Antilles

Tropical Storm Lee formed east of the Lesser Antilles on Tuesday afternoon. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Lee was located at latitude 13.2°N and longitude 41.8°W which put it about 1315 miles (2115 km) east of the Lesser Antilles. Lee was moving toward the west-northwest at 16 m.p.h. (26 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 1005 mb.

A low pressure system within a tropical wave over the Atlantic Ocean east of the Lesser Antilles strengthened on Tuesday afternoon and the U.S. National Hurricane Center designated the system as Tropical Storm Lee. More thunderstorms developed near the center of Lee’s circulation during the afternoon. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center started to generate upper level divergence that pumped mass away form the tropical storm. Winds to tropical storm force extended out 65 miles (105 km) from the center of Tropical Storm Lee.

Tropical Storm Lee will move through an environment favorable for intensification during the next 36 hours. Lee 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. Tropical Storm Lee will intensify during the next 36 hours. Lee could strengthen to a hurricane by Thursday.

Tropical Storm Lee will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Lee toward the west-northwest during the next 36 hours. On its anticipated track, Tropical Storm Lee could be northeast of the Leeward Islands by Friday night.

Tropical Depression Six Forms over the Atlantic

Tropical Depression Six formed over the Atlantic Ocean east of the Northern Leeward Islands on Saturday afternoon. At 5:00 p.m. EDT on Saturday the center of Tropical Depression Six was located at latitude 16.7°N and longitude 50.2°W which put it about 855 miles (1375 km) east of the Northern Leeward Islands. The tropical depression was moving toward the west-northwest at 16 m.p.h. (26 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 1006 mb.

A small area of low pressure over the Atlantic Ocean strengthened on Saturday afternoon and the U.S. National Hurricane Center designated the system as Tropical Depression Six. A distinct low level center of circulation was evident on visible satellite images of Tropical Depression Six. However, the distribution of thunderstorms was asymmetrical. Most of the thunderstorms were occurring in bands in the eastern side of the tropical depression. Bands in the western side of the circulation consisted primarily of showers and lower clouds. An upper level low east of Bermuda was producing westerly winds that were blowing toward the top of Tropical Depression Six. Those winds were causing strong vertical wind shear and the wind shear was causing the asymmetrical distribution of thunderstorms.

Tropical Depression Six will move through an environment that will be unfavorable for intensification during the next 36 hours. The tropical depression will move over water where the Sea Surface Temperatures are near 29°C. However, the upper level low east of Bermuda will continue to cause strong vertical wind shear. In addition, Tropical Depression Six will move into a region where there is drier air. The strong vertical wind shear and the drier air are likely to prevent Tropical Depression Six from intensifying to a tropical storm. The tropical depression could actually dissipate by early next week.

Tropical Depression Six will move around the southern side of a high pressure system over the Atlantic Ocean during the next 36 hours. The high pressure system will steer the tropical depression toward the west. On its anticipated track, Tropical Depression Six will move toward the Northern Leeward Islands.

Cindy Weakens to a Tropical Wave

Former Tropical Storm Cindy weakened to a tropical wave over the Atlantic Ocean south-southeast of Bermuda on Sunday night. At 11:00 p.m. EDT on Sunday the center of Tropical Wave Cindy was located at latitude 22.8°N and longitude 60.0°W which put it about 375 miles (605 km) north-northeast of the northern Leeward Islands. Former Tropical Storm Cindy 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 1011 mb.

An upper level trough over the western Atlantic Ocean produced southwesterly winds that blew toward the top of former Tropical Storm Cindy’s circulation. Those winds caused strong vertical wind shear. The wind shear blew the tops off of new thunderstorms that started to form near the center of circulation. Thunderstorms were still occurring in bands in the eastern half of the circulation around former Tropical Storm Cindy. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Winds to tropical storm force were occurring about 70 miles (110 km) northeast of the center of circulation. Winds in the other parts of former Tropical Storm Cindy were blowing at less than tropical storm force.

Former Tropical Storm Cindy will move through an environment unfavorable for intensification during the next 48 hours. Cindy will move over water where the Sea Surface Temperatures are near 28˚C. However, the upper level trough over the western Atlantic will cause strong vertical wind shear to continue for several more days. Former Tropical Storm Cindy could move into an area where there is less vertical wind shear in a couple of days. There is a slight chance that former Tropical Storm Cindy could strengthen when the wind shear decreases during the middle of the week.

Tropical Storm Fiona Prompts Warnings for Leeward Islands

A potential threat posed by Tropical Storm Fiona prompted the issuance of Tropical Storm Warnings for some of the Leeward Islands. At 11:00 a.m. EDT on Thursday the center of Tropical Storm Fiona was located at latitude 16.6°N and longitude 54.3°W which put it about 495 miles (800 km) east of the Leeward Islands. Fiona was moving toward the west at 14 m.p.h. (22 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 1002 mb.

Tropical Storm Warnings were in effect for Saba, St. Eustatius, St. Maarten, Antigua, Barbuda, St. Kitts, Nevis, Montserrat and Anguilla. Tropical Storm Watches were in effect for Guadeloupe, St. Martin and St. Barthelemy.

Tropical Storm Fiona was being affected by strong vertical wind shear on Thursday morning. The center of Fiona was surrounded by a swirl of showers and lower clouds. Thunderstorms were occurring in bands in the eastern edge of Fiona’s circulation. Tropical Storm Fiona was under the northern part of an upper level ridge over the tropical Atlantic Ocean. The upper level ridge was producing westerly winds that were blowing across the top of Fiona’s circulation. Those winds were causing strong vertical wind shear and the wind shear was blowing the tops off of many of the thunderstorms that start to develop. In spite of the vertical wind shear, the low level circulation around Tropical Storm Fiona was still well organized. Winds to tropical storm force extended out 140 miles (220 km) from the center of Fiona’s circulation.

Tropical Storm Fiona will move through an environment marginally favorable for intensification during the next 36 hours. Fiona will move over water where the Sea Surface Temperatures are near 28˚C. However, the upper level ridge over the tropical Atlantic Ocean will continue to cause vertical wind shear. The wind shear will inhibit intensification. Tropical Storm Fiona could weaken if the upper level winds get stronger. The upper level winds could be weaker when Fiona moves over the northeastern Caribbean Sea during the weekend.

Tropical Storm Fiona will move around the southern side of the subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Fiona toward the west during the next 36 hours. On its anticipated track Tropical Storm Fiona could approach the Leeward Islands on Friday afternoon. Fiona could bring gusty winds and locally heavy rain to the northern Leeward Islands. Tropical Storm Fiona could be southeast of Puerto Rico by Saturday evening.

TD 7 Strengthens to Tropical Storm Fiona, Watches Issued for Leeward Islands

Former Tropical Depression Seven strengthened to Tropical Storm Fiona on Wednesday evening and Tropical Storm Watches were issued for the Leeward Islands. At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Fiona was located at latitude 16.7°N and longitude 52.0°W which put it about 650 miles (1045 km) east of the Leeward Islands. Fiona was 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 1002 mb.

Tropical Storm Watches were in effect for Saba, St. Eustatius, St. Maarten, Antigua, Barbuda, St. Kitts, Nevis, Montserrat and Anguilla.

Remotely sensed data gathered by satellites indicated that the circulation around former Tropical Depression Seven had strengthened on Wednesday evening and the National Hurricane Center upgraded the system to Tropical Storm Fiona. The distribution of thunderstorms in Tropical Storm Fiona was asymmetric. Almost all of the thunderstorms were occurring in bands in the eastern half of Fiona’s circulation. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Storms in the eastern half of the circulation generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 140 miles (220 km) on the eastern side of Tropical Storm Fiona. The winds in the western half of the circulation were blowing at less than tropical storm force.

Tropical Storm Fiona will move through an environment somewhat favorable for intensification during the next 36 hours. Fiona will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the western part of an upper level ridge over the tropical Atlantic Ocean. The ridge will produce southwesterly winds that will blow toward the top of Fiona’s circulation. Those winds will cause some vertical wind shear and the wind shear will inhibit intensification. Tropical Storm Fiona could intensify if the upper level winds weaken.

Tropical Storm Fiona will move around the southern side of the subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Fiona toward the west during the next 48 hours. On its anticipated track Tropical Storm Fiona could approach the Leeward Islands on Friday afternoon. Fiona could bring gusty winds and locally heavy rain to the northern Leeward Islands.

Tropical Depression Seven Forms East of the Leeward Islands

Tropical Depression Seven formed east of the Leeward Islands on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Seven was located at latitude 16.6°N and longitude 49.6°W which put it about 805 miles (1300 km) east of the Leeward Islands. The tropical depression was moving toward the west at 14 m.p.h. (13 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 1009 mb.

A low pressure system over the Atlantic Ocean east of the Leeward Islands strengthened on Wednesday morning and the National Hurricane Center designated the system as Tropical Depression Seven. The distribution of thunderstorms in Tropical Depression Seven was asymmetric. Many of the thunderstorms were occurring in bands in the eastern half of the tropical depression. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Storms in the eastern half of the circulation generated upper level divergence that pumped mass away from the tropical depression.

Tropical Depression Seven will move through an environment somewhat favorable for intensification during the next 36 hours. The tropical depression will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the western part of an upper level ridge over the tropical Atlantic Ocean. The ridge will produce southerly winds that will blow toward the top of the tropical depression. Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but Tropical Depression Seven is likely to strengthen to a tropical storm.

Tropical Depression Seven will move around the southern side of the subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer the tropical depression toward the west during the next few days. On its anticipated track Tropical Depression Seven could approach the Leeward Islands on Friday afternoon. It could be a tropical storm when it approaches those islands.

Tropical Wave West of Africa Watched for Development

A tropical wave over the Atlantic Ocean west of Africa was being watched for development on Monday afternoon. The tropical wave was designated as Invest 97L on Monday. At 2:00 p.m. EDT on Monday the center of the tropical wave was located at latitude 11.7°N and longitude 22.7°W which put it about 230 miles (350 km) south of the Cabo Verde Islands. The tropical wave was moving toward the west at 19 m.p.h. (30 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). The minimum surface pressure was 1010 mb.

A tropical wave that moved over the Atlantic Ocean west of Africa during the weekend was being monitored for possible development of a tropical depression on Monday afternoon. The tropical wave exhibited a typical structure. There was no center of circulation evident in the lower levels of the atmosphere. There were linear bands of showers and thunderstorms that were moving with the tropical wave. Thunderstorms near the axis of the wave were generating upper level divergence that pumped mass away from the tropical wave.

The tropical wave will move through an environment favorable for the development of a tropical depression during the next several days. The tropical wave will move over water where the Sea Surface Temperatures are near 27˚C. It will move under the axis of an upper level ridge that extends from the west coast of Africa to the Caribbean Sea. The upper level winds are weak near the axis of the ridge. The tropical wave will move along the southern side of a subtropical pressure system over the Atlantic Ocean. The subtropical high is producing strong easterly winds in the lower level of the atmosphere. The strong low level winds may cause vertical wind shear in the lower levels of the atmosphere, which could inhibit the formation of a tropical depression. The National Hurricane Center is indicating that there is a probability of 40% of the formation of a tropical depression during the next five days.

The subtropical high pressure system will steer the tropical wave quickly toward the west-northwest during the next few days. On its anticipated track the tropical wave could approach the northern Leeward Islands in a few days. It could be a tropical depression or tropical storm by that time.

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.