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Tropical Storm Watches and Warnings Issued for Bahamas

Tropical Storm Watches and Warnings were issued for parts of the Bahamas on Friday afternoon because of a storm developing near the western end of Cuba.  The U.S. National Hurricane Center designated the developing storm as Potential Tropical Cyclone Nine.

At 5:00 p.m. EDT on Friday the center of Potential Tropical Cyclone Nine was located at latitude 20.9°N and longitude 74.6°W which put the center about 55 miles (90 km) north-northwest of the eastern end of Cuba.  Potential Tropical Cyclone Nine was moving toward the northwest at 9 m.p.h. (15 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.

Tropical Storm Warnings are in effect for the Central Bahamas including Cat Island, the Exumas, Long Island, Rum Cay, and San Salvador.

Tropical Storm Watches are in effect for the Northwestern Bahamas including Eleuthera, New Providence, the Abacos, the Berry Islands and Grand Bahama Island.

A surface low pressure system started to form on Friday afternoon in the northern end of a tropical wave near the eastern tip of Cuba.  The circulation around the low pressure system was still in the early stages of organization.  More thunderstorms started to develop near the center of the low pressure system.  Other thunderstorms started to form into bands that will begin to revolve around the center of circulation.

Potential Tropical Cyclone Nine will move through an environment that will be favorable for the formation of a tropical storm during the next 24 hours.  It will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the western side of an upper level ridge that is east of the Bahamas.  The upper level ridge will produce southerly winds that will blow toward the top of Potential Tropical Cyclone Nine.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Potential Tropical Cyclone Nine is likely to develop into a tropical storm on Saturday.

Potential Tropical Cyclone Nine will move around the western side of a high pressure system that is east of the Bahamas.  The high pressure system will steer Potential Tropical Cyclone Nine toward the north during the next 24 hours.  On its anticipated track, Potential Tropical Cyclone Nine will move across the Central Bahamas on Saturday night.  It will move across the Northwestern Bahamas on Sunday.

Potential Tropical Cyclone Nine will bring strengthening winds and locally heavy rain to the Central Bahamas and to the Northwestern Bahamas.

Elsewhere over the Atlantic Ocean, Hurricane Humberto rapidly intensified to a major hurricane northeast of the Leeward Islands and former Hurricane Gabrielle sped east of the Azores.

At 5:00 p.m. EDT on Friday the center of Hurricane Humberto was located at latitude 22.3°N and longitude 58.1°W which put the center about 430 miles (690 km) northeast of the Northern Leeward Islands.  Humberto was moving toward the west-northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (215 km/h).  The minimum surface pressure was 962 mb.

At 11:00 p.m. EDT on Friday the center of former Hurricane Gabrielle was located at latitude 40.0°N and longitude 22.8°W which put the center about 245 miles (395 km) east-northeast of Lajes Air Base, the Azores.  Gabrielle was moving toward the east-northeast at 31 m.p.h. (50 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.

Gabrielle Brings Wind and Rain to the Azores

Former Hurricane Gabrielle brought wind and rain to the Azores on Thursday night.  At 11:00 p.m. EDT on Thursday the center of former Hurricane Gabrielle was located at latitude 37.8°N and longitude 29.3°W which put the center about 65 miles (105 km) south-southwest of Faial Island, the Azores.  Gabrielle was moving toward the east-northeast at 29 m.p.h. (46 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.

A Hurricane Warning was in effect for all of the Azores.

Former Hurricane Gabrielle made a transition to a strong extratropical cyclone on Thursday.  Gabrielle moved over water where the Sea Surface Temperatures are near 23°C.  It moved under the southern extent of the upper level westerly winds in the middle latitudes.  Those upper level westerly winds cause strong vertical wind shear.  The cooler Sear Surface temperatures and strong vertical wind shear caused former Hurricane Gabrielle to make the transition to a strong extratropical cyclone.

The structure of former Hurricane Gabrielle changed as Gabrielle made the transition to an extratropical cyclone.  Winds to tropical storm force extended out 160 miles (260 km) from the center of Gabrielle’s circulation.

Former Hurricane Gabrielle will continue to produce strong winds and locally heavy rain in the Azores on Friday.  Heavy rain could cause floods in some locations.

The westerly winds in the middle latitudes will steer former Hurricane Gabrielle quickly toward the east during the next 24 hours.  On its anticipated track, Gabrielle could reach Portugal on Sunday.

Elsewhere over the Atlantic Ocean, Tropical Storm Humberto strengthened northeast of the Leeward Islands.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Humberto was located at latitude 22.2°N and longitude 57.1°W which put the center about 475 miles (765 km) northeast of the Northern Leeward Islands.  Humberto was moving toward the northwest at 3 m.p.h. (5 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 998 mb.

Hurricane Warning for Azores for Gabrielle

A Hurricane Warning is in effect for all of the Azores for Hurricane Gabrielle.  At 8:00 a.m. EDT on Wednesday the center of Hurricane Gabrielle was located at latitude 35.8°N and longitude 50.2°W which put the center about 1285 miles (2070 km) west of the Azores.  Gabrielle was moving toward the east-northeast at 25 m.p.h. (40 km/h).  The maximum sustained wind speed was 115 m.p.h. (1850 km/h) and there were wind gusts to 135 m.p.h. (220 km/h).  The minimum surface pressure was 960 mb.

A Hurricane Warning is in effect for all of the Azores.

Hurricane Gabrielle was speeding toward the Azores on Wednesday morning.  Gabrielle was still a major hurricane.  An eye was still present at the center of Gabrielle’s circulation, but there were some clouds in the eye.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Gabrielle’s circulation.  Storms near the center of Gabrielle generated upper level divergence that pumped mass away from the hurricane.  The removal of mass in the upper level was slightly less than the inflow of mass in the lower levels of the atmosphere.  The stronger inflow of mass in the lower levels caused the surface pressure to increase gradually.

The size of the circulation around Hurricane Gabrielle did not change much during the past 24 hours.  Winds to hurricane force extended out 45 miles (75 km) from the center of Gabrielle’s circulation.  Winds to tropical storm force extended out 140 miles (225 km) from the center of Hurricane Gabrielle.

The Hurricane Intensity Index (HII) for Hurricane Gabrielle is 20.6.  The Hurricane Size Index (HSI) is 15.5 and the Hurricane Wind Intensity Size Index (HWISI) is 36.1. Hurricane Gabrielle is similar in size and intensity to Hurricane Delta when Delta hit Louisiana in 2020.

Hurricane Gabrielle will move through an environment that will be unfavorable for intensification of a hurricane during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 26°C.  It will move under the southern extent of the upper level westerly winds in the middle latitudes.  Those upper level westerly winds will cause moderate vertical wind shear.  Hurricane Gabrielle will continue to weaken gradually during the next 24 hours.

The upper level westerly winds in the middle latitudes will steer Hurricane Gabrielle toward the east during the next 24 hours.  On its anticipated track, Hurricane Gabrielle will reach the Azores on Thursday.

Hurricane Gabrielle will bring strong winds and heavy rain to the Azores on Thursday night and Friday.

Gabrielle Prompts Hurricane Watch for the Azores

The risk posed by Hurricane Gabrielle prompted the issuance of a Hurricane Watch for the Azores on Tuesday.  At 2:00 p.m. EDT on Tuesday the center of Hurricane Gabrielle was located at latitude 34.3°N and longitude 57.5°W which put the center about 1710 miles (2755 km) west of the Azores.  Gabrielle was moving toward the east-northeast at 20 m.p.h. (32 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 952 mb.

A Hurricane Watch is in effect for all of the Azores.

A circular eye with a diameter of 20 miles (32 km) was at the center of Gabrielle’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 center of Gabrielle’s circulation.  Storms near the center of Gabrielle generated upper level divergence that pumped mass away from the hurricane.  The removal of mass in the upper level was slightly less than the inflow of mass in the lower levels of the atmosphere.  The strong inflow of mass in the lower levels caused the surface pressure to increase gradually.

The size of the circulation around Hurricane Gabrielle did not change much during the past 24 hours.  Winds to hurricane force extended out 40 miles (65 km) from the center of Gabrielle’s circulation.  Winds to tropical storm force extended out 140 miles (225 km) in the western side of Hurricane Gabrielle.  Winds to tropical storm force extended out 70 miles (110 km) in the eastern side of Gabrielle’s circulation.

The Hurricane Intensity Index (HII) for Hurricane Gabrielle was 25.1.  The Hurricane Size Index (HSI) was 12.9 and the Hurricane Wind Intensity Size Index (HWISI) was 38.0.  Hurricane Gabrielle was similar in size and intensity to Hurricane Harvey when Harvey hit Texas in 2017.

Hurricane Gabrielle will move through an environment that will become more unfavorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southern extent of the upper level westerly winds in the middle latitudes.  Those upper level westerly winds will cause the vertical wind shear to increase.  Hurricane Gabrielle will continue to weaken gradually during the next 24 hours.

The upper level westerly winds in the middle latitudes will steer Hurricane Gabrielle toward the east during the next 24 hours.  On its anticipated track, Hurricane Gabrielle will reach the Azores on Thursday.

Hurricane Gabrielle will bring strong winds and heavy rain to the Azores on Thursday night and Friday.

Hurricane Gabrielle Strengthens to Cat. 4

Hurricane Gabrielle strengthened to Category 4 on the Saffir-Simpson Scale east of Bermuda on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Hurricane Gabrielle was located at latitude 31.7°N and longitude 61.8°W which put the center about 180 miles (290 km) east-southeast of Bermuda.  Gabrielle was moving toward the north-northeast at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 165 m.p.h. (265 km/h).  The minimum surface pressure was 948 mb.

Hurricane Gabrielle strengthened to Category 4 on the Saffir-Simpson Scale east of Bermuda on Monday afternoon.  A circular eye with a diameter of 20 miles (32 km was at the center of Gabrielle’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 center of Gabrielle’s circulation.  Storms near the center of Gabrielle generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

The size of the circulation around Hurricane Gabrielle increased on Monday.  Winds to hurricane force extended out 40 miles (65 km) from the center of Gabrielle’s circulation.  Winds to tropical storm force extended out 140 miles (225 km) in the western side of Hurricane Gabrielle.  Winds to tropical storm force extended out 70 miles (110 km) in the eastern side of Gabrielle’s circulation.

The Hurricane Intensity Index (HII) for Hurricane Gabrielle was 28.6.  The Hurricane Size Index (HSI) was 13.1 and the Hurricane Wind Intensity Size Index (HWISI) was 41.7.

Hurricane Gabrielle will move through an environment that will become unfavorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southern extent of the upper level westerly winds in the middle latitudes.  Those upper level westerly winds will cause the vertical wind shear to increase.  Hurricane Gabrielle will start to weaken when the wind shear increases.

The upper level westerly winds in the middle latitudes will steer Hurricane Gabrielle toward the east during the next 24 hours.  On its anticipated track, Hurricane Gabrielle will move away from Bermuda on Tuesday.  Gabrielle will approach the Azores on Thursday.

 

Gabrielle Rapidly Intensifies to Major Hurricane

Hurricane Gabrielle rapidly intensified to a major hurricane southeast of Bermuda on Monday morning.  At 9:00 a.m. EDT on Monday the center of Hurricane Gabrielle was located at latitude 30.6°N and longitude 62.2°W which put the center about 195 miles (310 km) southeast of Bermuda.  Gabrielle was moving toward the north at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 145 m.p.h. (235 km/h).  The minimum surface pressure was 957 mb.

Hurricane Gabrielle rapidly intensified to a major hurricane southeast of Bermuda on Monday morning.  A small circular eye formed at the center of Gabrielle’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 center of Gabrielle’s circulation.  Storms near the center of Gabrielle generated strong upper level divergence that pumped mass away from the hurricane.  The removal of large quantities of mass caused the surface pressure to decrease rapidly.

The circulation around Hurricane Gabrielle became more symmetrical on Monday morning.  Winds to hurricane force extended out 30 miles (50 km) from the center of Gabrielle’s circulation.  Winds to tropical storm force extended out 140 miles (220 km) from the center of Hurricane Gabrielle.

The Hurricane Intensity Index (HII) for Hurricane Gabrielle was 22.1.  The Hurricane Size Index (HSI) was 9.9 and the Hurricane Wind Intensity Size Index (HWISI) was 32.0.  Hurricane Gabrielle was similar in size and intensity to Hurricane Dennis when Dennie hit Northwest Florida in 2005.

Hurricane Gabrielle will move through an environment favorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 29°C.  It will move in the region between an upper level low south of Bermuda and an upper level trough near the east coast of the U.S.  The upper level winds are weak between the upper level low and the upper level trough.  So, there will be little vertical wind shear. Hurricane Gabrielle will intensify during the next 24 hours.  Gabrielle could continue to intensify rapidly during the next few hours .

Hurricane Gabrielle will move around the western end of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Gabrielle toward the north during the next 24 hours.  On its anticipated track, Hurricane Gabrielle will pass east of Bermuda later on Monday.  Gabrielle could approach the Azores by Thursday evening.

Gabrielle Intensifies to a Hurricane

Former Tropical Storm Gabrielle intensified to a hurricane southeast of Bermuda on Sunday.  At 5:00 p.m. EDT on Sunday the center of Hurricane Gabrielle was located at latitude 28.5°N and longitude 61.7°W which put the center about 320 miles (515 km) southeast of Bermuda.  Gabrielle was moving toward the north-northwest at 10 m.p.h. (16 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 992 mb.

NOAA hurricane hunter aircraft conducting research flights into former Tropical Storm Gabrielle found that Gabrielle had intensified to a hurricane on Sunday afternoon.

The inner end of a rainband wrapped around the center of Hurricane Gabrielle.  A small eye appeared on microwave satellite imagery at the center of Gabrielle’s circulation.  Bands of showers and thunderstorms were revolving around the center of Hurricane Gabrielle.  Storms near the center of Gabrielle generated more upper level divergence that pumped mass away to the north and east of the tropical storm.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the northeastern part of Hurricane Gabrielle.  Winds to hurricane force extended out 25 miles (40 km) in the northeastern quadrant of Gabrielle’s circulation.  Winds to tropical storm force extended out 175 miles (280 km) in the eastern side of Hurricane Gabrielle.  Winds to tropical storm force extended out 70 miles (110 km) in the western half of Gabrielle’s circulation.

Hurricane Gabrielle will move through an environment favorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 29°C.  It will move in the region between an upper level low south of Bermuda and an upper level trough near the east coast of the U.S.  The upper level winds are weak between the upper level low and the upper level trough.  So, there will be little vertical wind shear.  Hurricane Gabrielle will intensify during the next 24 hours.  Gabrielle could intensify rapidly at times.

Hurricane Gabrielle will move around the western end of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer Gabrielle toward the north during the next 24 hours.  On its anticipated track, Hurricane Gabrielle will pass east of Bermuda on Monday.  Gabrielle could approach the Azores by late next week.

Tropical Storm Gabrielle Strengthens

Tropical Storm Gabrielle strengthened on Saturday as it moved over the Atlantic Ocean southeast of Bermuda.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Gabrielle was located at latitude 25.6°N and longitude 59.0°W which put the center about 580 miles (935 km) southeast of Bermuda.  Gabrielle was moving toward the northwest at 10 m.p.h. (16 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 996 mb.

Tropical Storm Gabrielle strengthened on Saturday.  The inner end of a rainband wrapped around the center of Gabrielle’s circulation.  A small eye was visible intermittently at the center of Gabrielle’s circulation.  Thunderstorms were occurring in bands in the northern and eastern parts of Tropical Storm Gabrielle.  Bands in the southern and western parts of Gabrielle’s circulation consisted primarily of showers and lower clouds.  Storms near the center of Gabrielle generated upper level divergence that pumped mass away to the north of the tropical storm.

The distribution of wind speeds in Tropical Storm Gabrielle continued to be asymmetrical.  Winds to tropical storm force extended out 140 miles (220 km) in the eastern side of Gabrielle’s circulation.  Winds to tropical storm force extended out 60 miles in the western side of Tropical Storm Gabrielle.

Tropical Storm Gabrielle will move through an environment that will be favorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the eastern side of an upper level low that is south of Bermuda.  The upper level low will produce southerly winds that will blow toward the top of Gabrielle’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Tropical Storm Gabrielle will intensify during the next 24 hours. Gabrielle is likely to strengthen to a hurricane on Sunday.

Tropical Storm Gabrielle will move around the southwestern part of a subtropical high pressure system over the eastern Atlantic Ocean.  The high pressure system will steer Gabrielle toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Gabrielle will pass east of Bermuda on Monday.  Gabrielle could approach the Azores by late next week.

Tropical Storm Gabrielle Moves Southeast of Bermuda

Tropical Storm Gabrielle moved southeast of Bermuda on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Gabrielle was located at latitude 22.4°N and longitude 56.6°W which put the center about 850 miles (1360 km) southeast of Bermuda.  Gabrielle was moving toward the west-northwest at 12 m.p.h. (19 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 1004 mb.

Tropical Storm Gabrielle started to exhibit more organization on Friday afternoon.  More thunderstorms formed near the center of Gabrielle’s circulation.  More thunderstorms also developed in bands in the eastern side of Tropical Storm Gabrielle.  Bands in the western side of Gabrielle still consisted primarily of showers and lower clouds.

The distribution of wind speeds in Tropical Storm Gabrielle continued to be asymmetrical.  Winds to tropical storm force extended out 150 miles (240 km) in the eastern side of Gabrielle’s circulation.  Winds to tropical storm force extended out 80 miles (130 km) in the western half of Gabrielle’s circulation.

Tropical Storm Gabrielle will move into an environment that will become more favorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the eastern side of an upper level low that is south of Bermuda.  The upper level low will produce southerly winds that will blow toward the top of Gabrielle’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Tropical Storm Gabrielle will intensify during the next 24 hours.  Gabrielle is likely to strengthen to a hurricane during the weekend.

Tropical Storm Gabrielle will move around the southwestern part of a subtropical high pressure system over the eastern Atlantic Ocean.  The high pressure system will steer Gabrielle toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Gabrielle will make its closest approach to Bermuda on Monday.

Tropical Storm Gabrielle Spins over the Central Atlantic

Tropical Storm Gabrielle was spinning over the Central Atlantic Ocean on Thursday.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Gabrielle was located at latitude 20.8°N and longitude 52.7°W which put the center about 700 miles (1125 km) east-northeast of the Northern Leeward Islands.  Gabrielle was moving toward the west-northwest at 13 m.p.h. (21 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 1004 mb.

The appearance of Tropical Storm Gabrielle did not change much on Thursday.  Gabrielle consisted of bands of showers and low clouds revolving around the center of circulation for much of Thursday.  New thunderstorms began to develop late Thursday afternoon in bands northeast of the center of Gabrielle’s circulation.  The bands in the other parts of Tropical Storm Gabrielle still consisted primarily of showers and lower clouds.

The distribution of wind speeds in Tropical Storm Gabrielle was very asymmetrical.  Winds to tropical storm force extended out 290 miles (465 km) in the northeastern quadrant of Gabrielle’s circulation.  Winds to tropical storm force extended out 175 miles (280 km) in the southeastern and northwestern quadrants of Gabrielle.  The winds in the southwestern quadrant of Tropical Storm Gabrielle were blowing at less than tropical storm force.

Tropical Storm Gabrielle will move through an environment that will be only marginally favorable for intensification during the next 24 hours.  Gabrielle will move over water where the Sea Surface Temperatures are near 28°C.  However, an upper level low that is northeast of the Northern Leeward Islands will produce strong southwesterly winds that will blow toward the top of Gabrielle’s circulation.  Those winds will cause strong vertical wind shear.  The strong vertical wind shear will prevent significant intensification during the next 24 hours.  The wind shear is forecast to decrease during the weekend and Tropical Storm Gabrielle is likely to intensify when the shear decreases.

Tropical Storm Gabrielle will move around the southwestern part of a subtropical high pressure system over the eastern Atlantic Ocean.  The high pressure system will steer Gabrielle toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Gabrielle will pass northeast of the Leeward Islands on Friday night.