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Rafael Weakens to a Tropical Storm

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Former Hurricane Rafael weakened to a tropical storm over the central Gulf of Mexico on Friday night.  At 4:00 a.m. EST on Saturday the center of Tropical Storm Rafael was located at latitude 25.0°N and longitude 90.8°W which put the center about 265 miles (425 km) north-northwest of Progreso, Mexico.  Rafael was moving toward the west-northwest 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 992 mb.

Former Hurricane Rafael continued to weaken over the central Gulf of Mexico on Friday night. An upper level low over the central U.S. was producing southwesterly winds that were blowing toward the top of Rafael’s circulation.  Those winds were causing moderate vertical wind shear. Drier air was being pulled into the western side of Tropical Storm Rafael.  The combination of moderate vertical wind shear and drier air caused Rafael to continue to weaken.

The moderate vertical wind shear was also affecting the structure of Tropical Storm Rafael.  New thunderstorms were still developing near the center of Rafael’s circulation.  Thunderstorms were also still occurring in bands in the eastern side of Tropical Storm Rafael.  Bands in the western side of Rafael’s circulation consisted primarily of showers and lower clouds.   Storms near the center of Rafael generated upper level divergence that pumped mass away to the east of the tropical storm.

The circulation around Tropical Storm Rafael was small. Wind to tropical storm force extended out 90 miles (145 km) from the center of Rafael’s circulation.

Tropical Storm Rafael will move through an environment mostly unfavorable for intensification during the next 24 hours.  Rafael will move over water where the Sea Surface Temperatures are near 29°C.  However the upper level low over the central U.S. will continue to cause moderate vertical wind shear.  More drier air will also get pulled into the western side of Rafael’s circulation.  The combination of moderate vertical wind shear and drier air is likely to cause Tropical Storm Rafael to weaken gradually during the next 24 hours.  Rafael could maintain its intensity today, if the wind shear does not get any stronger.

The winds steering Tropical Storm Rafael will be weak during the next 24 hours. As a result, on its anticipated track, Rafael will meander over the central Gulf of Mexico during the weekend.

Hurricane Rafael Weakens Over Gulf of Mexico

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Hurricane Rafael weakened over the central Gulf of Mexico on Friday.  At 4:00 p.m. EST on Friday the center of Hurricane Rafael was located at latitude 24.6°N and longitude 89.7°W which put the center about 230 miles (365 km) north of Progreso, Mexico.  Rafael was moving toward the west at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 967 mb.

Hurricane Rafael started to weaken over the central Gulf of Mexico on Friday afternoon.  An upper level low over the central U.S. was producing southwesterly winds that were blowing toward the top of Rafael’s circulation.  Those winds were causing moderate vertical wind shear.  Drier air was being pulled into the western side of Hurricane Rafael.  The combination of moderate vertical wind shear and drier air caused Hurricane Rafael to start to weaken.

The moderate vertical wind shear was also affecting the structure of Hurricane Rafael.  An eye was no longer visible at the center of Rafael’s circulation.  The western part of the former eyewall weakened and that part of the eyewall consisted of showers and lower clouds.  Thunderstorms were still occurring in the eastern part of the former eyewall.  Thunderstorms were also still occurring in bands in the eastern side of Hurricane Rafael.  Storms near the center of Rafael generated upper level divergence that pumped mass away to the east of the hurricane.

The circulation around Hurricane Rafael was small.  Winds to hurricane force extended out 30 miles (50 km) from the center of Rafael’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Hurricane Rafael.

The Hurricane Intensity Index (HII) for Hurricane Rafael was 16.5. The Hurricane Size Index (HSI) was 10.5 and the Hurricane Wind Intensity Size Index (HWISI) was 27.0.  Hurricane Rafael was similar in intensity to Hurricane Idalia when Idalia hit Florida in 2023.  Rafael was bigger than Idalia was.

Rafael will move into an environment unfavorable for intensification during the next 24 hours.  Rafael will move over water where the Sea Surface Temperatures are near 29°C.  However the upper level low over the central U.S. will continue to cause moderate vertical wind shear.  More drier air will also get pulled into the western side of Rafael’s circulation.  The combination of moderate vertical wind shear and drier air will cause Hurricane Rafael to weaken during the next 24 hours.

The winds steering Hurricane Rafael will weaken during the next 24 hours.  As a result, on its anticipated track, Hurricane Rafael will meander over the central Gulf of Mexico during the weekend.

Hurricane Rafael Moves Over Southeastern Gulf of Mexico

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Hurricane Rafael moved over the southeastern Gulf of Mexico on Thursday.  At 4:00 p.m. EST on Thursday the center of Hurricane Rafael was located at latitude 24.7°N and longitude 86.2°W which put the center about 325 miles (520 km) northeast of Progreso, Mexico.  Rafael was moving toward the west-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 968 mb.

Hurricane Rafael weakened a little on Wednesday night as it moved across western Cuba.  Rafael strengthened again on Thursday when it moved over the southeastern Gulf of Mexico.  The inner end of a rainband wrapped around the center of Rafael’s circulation and an eye formed again at the center of Hurricane Rafael.  Bands of showers and thunderstorms were revolving around the core of Rafael’s circulation.  Storms near the core of Rafael generated upper level divergence that pumped more mass away from the hurricane. The removal of more mass caused the surface pressure to decrease.

The circulation around Hurricane Rafael was small.  Wind to hurricane force extended out 30 miles (50 km) from the center of Rafael’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) from the center of Hurricane Rafael.

The Hurricane Intensity Index (HII) for Hurricane Rafael was 17.8.  The Hurricane Size Index (HSI) was 10.0 and the Hurricane Wind Intensity Size Index (HWISI) was 27.8.  Hurricane Rafael was similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

Rafael will move into an environment favorable for intensification during the next 24 hours.  Rafael will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the eastern periphery of a large upper level trough that extends from the North Central U.S. to the Southwest U.S.  The upper level trough will produce southwesterly winds that will blow toward the top of Rafael’s circulation. Those winds will cause some vertical wind shear, but the wind shear may not be enough to prevent intensification.  Hurricane Rafael could intensify during the next 24 hours.  The wind shear is likely to increase during the weekend and Rafael is likely to weaken when the shear increases.

Hurricane Rafael will move around the southwestern part of a high pressure system that extends from the western Atlantic Ocean to the Gulf of Mexico.  The high pressure system will steer Rafael toward the west during the next 24 hours.  On its anticipated track, Hurricane Rafael will move toward the central Gulf of Mexico.

Hurricane Rafael Hits Western Cuba

Hurricane Rafael hit western Cuba late on Wednesday afternoon.  At 4:00 p.m. EST on Wednesday the center of Hurricane Rafael was located at latitude 22.6°N and longitude 82.7°W which put the center about 45 miles (75 km) south-southwest of Havana, Cuba.   Rafael was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (220 km/h).  The minimum surface pressure was 950 mb.

A  Hurricane Warning is in effect for the Cuban provinces of Pinar del Rio, Artemisa, La Habana, Mayabeque, Matanzas, and the Isle of Youth.

A Tropical Storm Warning is in effect for the Cuban provinces of Villa Clara, and Cienfuegos.  A Tropical Storm Warning is in effect for the Florida Keys from Key West to Channel 5 Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas. 

Hurricane Rafael intensified to a major hurricane on Wednesday before it hit western Cuba.  Concentric eyewalls formed in the core of Rafael’s circulation.  An eyewall replacement cycle started, but the inner eyewall was still intact when Hurricane Rafael hit western Cuba.  Since the inner eyewall was still intact, Rafael did not weaken before it hit Cuba.

Bands of showers and thunderstorms were revolving around the concentric eyewalls.  Storms near the core of Rafael generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The circulation around Hurricane Rafael was small.  Wind to hurricane force extended out 30 miles (50 km) from the center of Rafael’s circulation.  Winds to tropical storm force extended out 115 miles (185 km) in the eastern side of Hurricane Rafael.  Winds to tropical storm force extended out 60 miles (95 km) in the western side of Rafael.

The Hurricane Intensity Index (HII) for Hurricane Rafael was 20.6.  The Hurricane Size Index (HSI) was 8.8 and the Hurricane Wind Intensity Size Index (HWISI) was 29.4.  Hurricane Rafael was similar in intensity to Hurricane Delta when Delta hit Louisiana in 2020.  Rafael was not as big as Delta was.

Hurricane Rafael will move around the southwestern part of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Rafael toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Hurricane Rafael will move across western Cuba during the next few few hours.  Rafael will move over the southeastern Gulf of Mexico on Thursday.

Hurricane Rafael will bring strong winds and heavy rain to western Cuba.  Strong winds could cause widespread electricity outages in Cuba.  Heavy rain will cause flash floods in some locations.  Rafael could cause a storm surge of up to 10 feet (3 meters) along the south coast of western Cuba.  Hurricane Rafael will be capable of causing localized major damage.

Hurricane Rafael will weaken as it moves across western Cuba.  Rafael will move into an environment somewhat favorable for intensification after it moves north of Cuba.  Rafael will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the eastern periphery of a large upper level trough that extends from the North Central U.S. to the Southwest U.S.  The upper level trough will produce southwesterly winds that will blow toward the top of Rafael’s circulation.  Those winds will cause the vertical wind shear to increase but the wind shear may not be enough to prevent intensification.  Hurricane Rafael will could intensify on Thursday after it moves north of Cuba.

Hurricane Rafael Approaches Western Cuba

Hurricane Rafael was approaching western Cuba on Wednesday morning.  At 10:00 a.m. EST on Wednesday the center of Hurricane Rafael was located at latitude 21.4°N and longitude 81.9°W which put the center about 130 miles (210 km) south-southeast of Havana, Cuba.  Rafael was moving toward the northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 960 mb.

A  Hurricane Warning is in effect for the Cuban provinces of Pinar del Rio, Artemisa, La Habana, Mayabeque, Matanzas, and the Isle of Youth.

A Tropical Storm Warning is in effect for the Cuban provinces of Villa Clara, Cienfuegos, Sancti Spiritis, and Ciego de Avila.

A Tropical Storm Watch is in effect for the Florida Keys from Key West to Channel 5 Bridge.  A Tropical Storm Watch is in effect for the Dry Tortugas. 

Hurricane Rafael began to intensify more rapidly on Wednesday morning.  Two concentric eyewalls formed at the center of Rafael’s circulation.  A small inner eye was at the center of Hurricane Rafael.  The inner eye was surrounded by a tight ring of thunderstorms and the strongest winds were occurring in that ring of storms.  The inner end of a rainband wrapped around the inner eye and eyewall and a larger, outer eyewall formed.  Bands of showers and thunderstorms were revolving around the concentric eyewalls.  Storms near the core of Rafael generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The circulation around Hurricane Rafael was small.  Wind to hurricane force extended out 20 miles (30 km) from the center of Rafael’s circulation.  Winds to tropical storm force extended out 115 miles (185 km) in the eastern side of Hurricane Rafael.  Winds to tropical storm force extended out 60 miles (95 km) in the western side of Rafael.

The Hurricane Intensity Index (HII) for Hurricane Rafael was 19.2.  The Hurricane Size Index (HSI) was 6.8 and the Hurricane Wind Intensity Size Index (HWISI) was 26.0.  Hurricane Rafael was similar in intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.  Rafael was not as big as Zeta was.

Hurricane Rafael will move through an environment favorable for intensification during the next few hours.  Rafael will move over water where the Sea Surface Temperatures are near 29°C. It will move under the middle of an upper level ridge over the Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Hurricane Rafael will intensify during the next few hours.  Rafael is likely to strengthen to a major hurricane.

Hurricane Rafael will move around the southwestern part of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Rafael toward the northwest during the next 24 hours.  On its anticipated track, the center of Hurricane Rafael will reach western Cuba in a few hours.

Hurricane Rafael will bring strong winds and heavy rain to western Cuba.  Strong winds could cause widespread electricity outages in Cuba.  Heavy rain will cause flash floods in some locations.  Rafael could cause a storm surge of up to 10 feet (3 meters) along the south coast of western Cuba.  Hurricane Rafael will be capable of causing localized major damage.

Rafael Intensifies to a Hurricane Near Cayman Islands

Former Tropical Storm Rafael intensified to a hurricane near the Cayman Islands on Tuesday evening.  At 10:00 p.m. EST on Tuesday the center of Hurricane Rafael was located at latitude 19.7°N and longitude 80.4°W which put the center about 60 miles (95 km) east-northeast of Grand Cayman.  Rafael was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (150 km/h).  The minimum surface pressure was 985 mb.

A Hurricane Warning was in effect for Grand Cayman, Little Cayman, and Cayman Brac.  A  Hurricane Warning was in effect for the Cuban provinces of Pinar del Rio, Artemisa, La Habana, Mayabeque, Matanzas, and the Isle of Youth.

A Tropical Storm Warning was in effect for the Cuban provinces of Villa Clara, Cienfuegos, Sancti Spiritis, and Ciego de Avila.

A Tropical Storm Watch was in effect for the Florida Keys from Key West to Channel 5 Bridge.  A Tropical Storm Watch was in effect for the Dry Tortugas.  A Tropical Storm Watch was in effect for the Cuban provinces of Camaguey and Las Tunas.

Former Tropical Storm Rafael intensified to a hurricane on Tuesday evening.  A circular eye with a diameter of 15 miles (17 km) formed at the center of Rafael’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Hurricane Rafael.  Storms near the core of Rafael generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

Winds to hurricane force extended out 20 miles (30 km) in the northeastern quadrant of Hurricane Rafael.  Wind to tropical storm force extended out 115 miles (185 km) in the eastern side of Rafael’s circulation.  Winds to tropical storm force extended out 60 miles (95 km) in the western side of Hurricane Rafael.

Hurricane Rafael will move through an environment favorable for intensification during the next 24 hours.  Rafael will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge over the Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Hurricane Rafael will intensify during the next 24 hours.  Rafael could intensify rapidly at times.

Hurricane Rafael will move around the southwestern part of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Rafael toward the northwest during the next 24 hours.  On its anticipated track, the center of Hurricane Rafael will move away from the Cayman Islands.  Rafael is likely to reach western Cuba by Wednesday afternoon.

Hurricane Rafael will continue to bring strong winds and heavy rain to the Cayman Islands for the next few hours.  Heavy rain could cause floods in some locations. Rafael could also cause a storm surge of up to 7 feet (2 meters) in the Cayman Islands.  Hurricane Rafael will bring strong winds and heavy rain to western Cuba.  Strong winds could cause widespread electricity outages in Cuba.  Heavy rain could cause flash floods in some locations.  Rafael could cause a storm surge of up to 10 feet (3 meters) along the south coast of western Cuba.

Tropical Storm Rafael Brings Wind and Rain to Jamaica

Tropical Storm Rafael was bringing wind and rain to Jamaica on Tuesday morning.  The center of Rafael was just southwest of Jamaica.  At 7:00 a.m. EST on Tuesday the center of Tropical Storm Rafael was located at latitude 17.4°N and longitude 78.4°W which put the center about 80 miles (130 km) south-southwest of Montego Bay, Jamaica.  Rafael was moving toward the northwest at 13 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 993 mb.

A Hurricane Warning was in effect for Grand Cayman, Little Cayman, and Cayman Brac.  A  Hurricane Warning was in effect for the Cuban provinces of Pinar del Rio, Artemisa, La Habana, Mayabeque, Matanzas, and the Isle of Youth.

A Tropical Storm Warning was in effect for Jamaica. A Tropical Storm Warning was in effect for the Cuban provinces of Villa Clara, Cienfuegos, Sancti Spiritis, and Ciego de Avila.

A Tropical Storm Watch was in effect for the Florida Keys from Key West to Channel 5 Bridge.  A Tropical Storm Watch was in effect for the Dry Tortugas.  A Tropical Storm Watch was in effect for the Cuban provinces of Camaguey and Las Tunas.

Tropical Storm Rafael was strengthening on Tuesday morning as it passed near Jamaica.  The inner end of a rainband wrapped around the western and southern sides of the center of Rafael’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Rafael.  Storms near the center of Rafael generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds around Tropical Storm Rafael was asymmetrical.  Winds to tropical storm force extended out 105 miles (165 km) in the eastern side of Rafael’s circulation.  The winds in the western side of Tropical Storm Rafael were blowing at less than tropical storm force.

Tropical Storm Rafael will move through an environment favorable for intensification during the next 24 hours.  Rafael will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge over the Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear. Tropical Storm Rafael will intensify during the next 24 hours.  Rafael could intensify rapidly at times.  Tropical Storm Rafael is likely to strengthen to a hurricane by Tuesday night.

Tropical Storm Rafael will move around the southwestern part of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Rafael toward the northwest during the next 24 hours.  On its anticipated track, the center of Tropical Rafael will reach the Cayman Islands by Tuesday night.  Rafael is likely to reach western Cuba by Wednesday afternoon.

Tropical Storm Rafael will continue to bring strong winds and heavy rain Jamaica for the rest of Tuesday.  Heavy rain is likely to cause floods in some locations.  Rafael is likely to be a hurricane when it moves over the Cayman Islands.  Rafael will bring strong winds and heavy rain to the Cayman Islands.  It could also cause a storm surge of up to 7 feet (2 meters) in the Cayman Islands.  Rafael will be a hurricane when it reaches western Cuba.  Strong winds could cause widespread electricity outages in Cuba.  Heavy rain could cause flash floods in some locations.

Depression Strengthens to Tropical Storm Rafael

Former Tropical Depression Eighteen strengthened to Tropical Storm Rafael south of Jamaica on Monday afternoon.  At 4:00 p.m. EST on Monday the center of Tropical Storm Rafael was located at latitude 15.5°N and longitude 76.7°W which put the center about 175 miles (280 km) south of Kingston, Jamaica.  Rafael was moving toward the north at 9 m.p.h. (15 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.

A Hurricane Warning was in effect for Grand Cayman, Little Cayman, and Cayman Brac,

A Tropical Storm Warning was in effect for Jamaica.

A Hurricane Watch was in effect for the Cuban provinces of Pinar del Rio, Artemisa, La Habana, Mayabeque, Matanzas, and the Isle of Youth.

A Tropical Storm Watch was in effect for the Florida Keys from Key West to Channel 5 Bridge.  A Tropical Storm Watch was in effect for the Dry Tortugas.  A Tropical Storm Watch was in effect for the Cuban provinces of Villa Clara, Cienfuegos, Sancti Spiritis, Ciego de Avila, Camaguey and Las Tunas.

Former Tropical Depression Eighteen strengthened on Monday afternoon and the U.S. National Hurricane Center designated the system as Tropical Storm Rafael.  The circulation around Tropical Storm Rafael was organizing rapidly.  The inner end of a rainband wrapped around the center of Rafael’s circulation.  More thunderstorms formed near the center of circulation.  More thunderstorms also developed in bands revolving around the center of Tropical Storm Rafael.  Storms near the center of Rafael generated upper level divergence that pumped mass away fro the tropical storm.  The removal of mass caused the surface pressure to decrease.

Tropical Storm Rafael will move through an environment favorable for intensification during the next 24 hours.  Rafael will move over water where the Sea Surface Temperatures are near 29°C. It will move under the middle of an upper level ridge over the Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Storm Rafael will intensify during the next 24 hours.  Rafael could intensify rapidly at times.  Tropical Storm Rafael is likely to strengthen to a hurricane on Tuesday.

Tropical Storm Rafael will move around the southwestern part of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Rafael toward the northwest during the next 24 hours.  On its anticipated track, the center of Tropical Rafael will pass near Jamaica on Monday night.  Rafael  will reach the Cayman Islands by Tuesday night.  Rafael is likely to reach western Cuba by Wednesday afternoon.

Tropical Storm Rafael will bring strong winds and heavy rain Jamaica. Heavy rain is likely to cause floods in some locations.  Rafael is likely to be a hurricane when it moves over the Cayman Islands.  Rafael will bring strong winds and heavy rain to the Cayman Islands.  It could also cause a storm surge of up to 7 feet (2 meters) in the Cayman Islands.

Tropical Storm Warning Issued for Jamaica, Hurricane Watch for Cayman Islands

The threat posed by a low pressure system over the Southwestern Caribbean Sea prompted the issuance of a Tropical Storm Warning for Jamaica and a Hurricane Watch for the Cayman Islands on Sunday afternoon.  The low pressure system was designated as Potential Tropical Cyclone Eighteen by the U.S. National Hurricane Center.  At 4:00 p.m. EST on Sunday the center of Potential Tropical Cyclone Eighteen was located at latitude 13.0°N and longitude 77.1°W which put the center about 345 miles (555 km) south of Kingston, Jamaica.  The low pressure system was moving toward the northeast 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 1004 mb.

A Hurricane Watch is in effect for Grand Cayman, Little Cayman, and Cayman Brac.

A Tropical Storm Warning is in effect for Jamaica.

A U.S. Air Force Reserve Hurricane Hunter aircraft investigated a low pressure system over the Southwestern Caribbean Sea on Sunday afternoon.  The aircraft found that there was a distinct low low level center of circulation in the low pressure system.  More thunderstorms were forming near the center of the low pressure system.  Bands of showers and thunderstorms were starting to revolve around the center of Potential Tropical Cyclone Eighteen.  Storms near the center of the low pressure system began to generate upper level divergence.

Potential Tropical Cyclone Eighteen will move through an environment favorable for intensification during the next 24 hours.  The low pressure system will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the western end of an upper level ridge over the Caribbean Sea.  The upper level ridge will produce southeasterly winds that will blow toward the top of the low pressure system.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Potential Tropical Cyclone Eighteen will intensify during the next 24 hours.  It is likely to become a tropical storm on Monday.

Potential Tropical Cyclone Eighteen will move around the southwestern part of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Potential Tropical Cyclone Eighteen toward the north-northwest during the next 24 hours.  On its anticipated track, Potential Tropical Cyclone Eighteen will reach Jamaica on Monday night.  It could reach the Cayman Islands on Tuesday afternoon.

Potential Tropical Cyclone Eighteen will bring strong winds and heavy rain Jamaica and the Cayman Islands.  Heavy rain is likely to cause floods in some locations.

Elsewhere, Subtropical Storm Patty moved east of the Azores.  At 4:00 p.m. EST on Sunday the center of Subtropical Storm Patty was located at latitude 37.3°N and longitude 22.3°W which put the center about 280 miles (450 km) east-southeast of Lajes, Azores.  Patty was moving toward the east 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 Philippe Prompts Watches for Antigua and Barbuda

A potential risk caused by Tropical Storm Philippe prompted the issuance of Tropical Storm Watches for Antigua and Barbuda on Sunday. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Philippe was located at latitude 16.6°N and longitude 59.1°W which put it about 155 miles (245 km) east of Guadeloupe. Philippe was moving toward the west-northwest at 5 m.p.h. (8 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 998 mb.

Tropical Storm Watches were in effect for Antigua and Barbuda.

Tropical Storm Philippe did not move much on Sunday. The circulation around Philippe also did not change much on Sunday. An upper level ridge over the eastern Caribbean Sea continued to produce northwesterly winds that blew toward the top of Philippe’s circulation. Those winds caused strong vertical wind shear. The vertical wind shear caused the distribution of thunderstorms in Tropical Storm Philippe to be asymmetrical. Most of the thunderstorms were occurring in bands in the southeastern part of Philippe’s circulation. Bands near the center of Tropical Storm Philippe and in the other parts of the circulation consisted primarily of showers and lower clouds. The distribution of wind speeds was also asymmetrical. Winds to tropical storm force extended out 170 miles (275 km) in the eastern side of Philippe’s circulation. The winds in the western side of Tropical Storm Philippe were blowing at less than tropical storm force.

Tropical Storm Philippe will move through a region that will be unfavorable for intensification during the next 24 hours. Philippe will move over water where the Sea Surface Temperatures are near 29°C. However, the upper level ridge over the eastern Caribbean Sea will continue to cause strong vertical wind shear. The wind shear is likely to prevent intensification of Tropical Storm Philippe on Monday.

Tropical Storm Philippe will move around the southwestern part of a high pressure system over the Atlantic Ocean. The high pressure system will steer Philippe toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Philippe could move a little closer to Antigua and Barbuda on Monday.

Elsewhere over the Atlantic Ocean, former Tropical Storm Rina weakened to a tropical depression northeast of the Leeward Islands. At 11:00 p.m. EDT on Sunday the center of Tropical Depression Rina was located at latitude 27.1°N and longitude 55.4°W which put it about 785 miles (1265 km) northeast of the Northern Leeward Islands. Rina was moving toward the north at 13 m.p.h. (21 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.

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