Tag Archives: Bermuda

Tropical Storm Chantal Forms Southeast of Nova Scotia

Tropical Storm Chantal formed southeast of Nova Scotia on Tuesday night.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Chantal was located at latitude 40.2°N and longitude 56.2°W which put it about 485 miles (780 km) southeast of Halifax, Nova Scotia.  Chantal was moving toward the east at 22 m.p.h. (35 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 small low pressure system that was near the coast of the Carolinas during the weekend began to exhibit tropical characteristics on Tuesday night and the National Hurricane Center designated the system as Tropical Storm Chantal.  Thunderstorms developed closer to the center of circulation when the low moved near the Gulf Stream and the strongest winds were occurring closer to the center.  Although the circulation around Chantal looked more tropical, the distribution of thunderstorms was still asymmetrical.  Many of the stronger storms were occurring in the eastern half of the circulation.  Bands in the western half of the circulation consisted primarily of showers and lower clouds.  Tropical Storm Chantal was far enough north that it was in the region of westerly winds in the upper levels.  Those winds were causing moderate vertical wind shear and they were the primary reason for the asymmetrical distribution of thunderstorms.

Tropical Storm Chantal will move through an environment only marginally favorable for intensification during the next several days.  Chantal will move over water where the Sea Surface Temperature is near 25°C.  It will continue to be in a region of moderate westerly winds in the upper levels, which will cause vertical wind shear.  Tropical Storm Chantal could intensify slowly if the upper level winds do not get any stronger.  However, Chantal could weaken if the upper level winds do get stronger.

Tropical Storm Chantal will move around the northern end of a ridge in the middle troposphere over the Atlantic Ocean.  The ridge will steer Chantal toward the east during the next 24 hours.  Chantal could move more toward the southeast on Thursday when it nears the western end of the ridge.  On its anticipated track Tropical Storm Chantal is forecast to make a slow loop in the middle of the Atlantic Ocean.

Subtropical Storm Andrea Develops Southwest of Bermuda

Subtropical Storm Andrea developed southwest of Bermuda on Monday afternoon.  An Air Force Reserve Hurricane Hunter aircraft investigated an area of low pressure southwest of Bermuda on Monday afternoon.  The aircraft determined that there was a well defined center of circulation at the surface and the National Hurricane Center designated the system as Subtropical Storm Andrea.  At 11:00 p.m. EDT on Monday the center of Subtropical Storm Andrea was located at latitude 29.5°N and longitude 68.7°W which put it about 300 miles (485 km) southwest of Bermuda.  Andrea was moving toward the north at 12 m.p.h. (19 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 1006 mb.

The circulation around Subtropical Storm Andrea was asymmetrical.  Most of the thunderstorms and the strongest winds were occurring northeast of the center of circulation.  Bands in other parts of the circulation consisted primarily of lower clouds and showers and the winds were weaker in those parts of Andrea.  An upper low northeast of the Bahamas was producing southerly winds which were blowing toward the top of the circulation.  Those winds were creating moderate vertical wind shear and the shear was the primary cause of the asymmetrical structure of Subtropical Storm Andrea.  The asymmetrical structure was the reason why Andrea was classified as a subtropical storm.  Winds to tropical storm force extended out about 65 miles (105 km) from the center of Andrea in the northeastern quadrant of the circulation.

Subtropical Storm Andrea will move through an environment marginally favorable for intensification on Tuesday.  Andrea will move over water where the Sea Surface Temperature is near 25°C.  The upper low will continue to cause moderate vertical wind shear, but the low could weaken slightly on Tuesday.  If the upper level winds weaken, then Andrea could get stronger.  Stronger upper level westerly winds could affect Subtropical Storm Andrea on Wednesday.  Those winds will cause stronger vertical wind shear which will weaken Andrea.

The upper level low northeast of the Bahamas will steer Subtropical Storm Andrea toward the north during the next 12-18 hours.  After that time the upper level westerly winds are likely to steer Andrea more toward the east.  On its anticipated track Subtropical Storm Andrea could be near Bermuda in about 36 hours.  Andrea could bring gusty winds and rain showers to Bermuda on Wednesday.

Oscar Strengthens Into a Hurricane Southeast of Bermuda

One time subtropical storm and former Tropical Storm Oscar strengthened into a hurricane southeast of Bermuda on Sunday.  At 5:00 p.m. EDT on Sunday the center of Hurricane Oscar was located at latitude 25.7°N and longitude 55.5°W which put it about 725 miles (1165 km) southeast of Bermuda.  Oscar was moving toward the west at 16 m.p.h. (26 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 989 mb.

A small eye formed at the center of former Tropical Storm Oscar and the National Hurricane Center upgraded Oscar to a hurricane.  A thin ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several short bands of showers and thunderstorms were revolving around the core of Hurricane Oscar.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.

The circulation around Hurricane Oscar is relatively small.  Winds to hurricane force extend out only about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extend out about 115 miles (185 km) from the center.

Hurricane Oscar will move through an environment favorable for intensification for another day or two.  Oscar will move over water where the Sea Surface Temperature is near 27°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Because of its relatively small circulation, Hurricane Oscar could intensify rapidly while it is in a favorable environment.  Oscar will get stronger during the next 36 to 48 hours and some models are forecasting that it will become a major hurricane.  An upper level trough moving off the East Coast of the U.S. will produce southwesterly winds which will cause the vertical wind shear to increase by Wednesday.

Hurricane Oscar will move around the western end of a ridge of high pressure over the Atlantic Ocean on Monday and Tuesday.  The ridge will steer Oscar toward the west for another 12 to 24 hours.  Hurricane Oscar will move more toward the north when it reaches the western end of the ridge.  On its anticipated track Hurricane Oscar will pass east of Bermuda on Tuesday.  The upper level trough will steer Oscar rapidly toward the northeast on Wednesday.

Oscar Transitions to a Tropical Storm

Former Subtropical Storm Oscar transitioned to a tropical storm on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Oscar was located at latitude 25.7°N and longitude 51.4°W which put it about 930 miles (1495 km) east-southeast of Bermuda.  Oscar was moving toward the west-southwest at 20 m.p.h. (32 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 994 mb.

The structure of the circulation of former Subtropical Storm Oscar changed to a shape more like a tropical cyclone and the National Hurricane Center reclassified Oscar as a tropical storm.  A band of showers and thunderstorms wrapped more tightly around the eastern side of the center of circulation.  The strongest winds were occurring about 30 miles (50 km) from the center.  Other bands of showers and thunderstorms were starting to form in the eastern half of the circulation.

Tropical Storm Oscar will move through an environment somewhat favorable for intensification during the next 36 hours.  Oscar will move over water where the Sea Surface Temperature is near 27°C.  An upper level low southeast of Oscar will produce northerly winds which will blow toward the top of the tropical storm.  However, the core of Tropical Storm Oscar will remain south of the strongest upper level winds on Sunday.  Tropical Storm Oscar could intensify into a hurricane by Monday.

The upper level low is steering Tropical Storm Oscar quickly toward the west-southwest.  That motion is forecast to continue for anther 24 hours.  A large upper level trough over the eastern U.S.  will produce southwesterly winds which will start to turn Oscar toward the northeast in about 36 to 48 hours.  On its anticipated track Tropical Storm Oscar could be southeast of Bermuda on Monday night.

Subtropical Storm Oscar Develops East of Bermuda

Subtropical Storm Oscar developed east of Bermuda on Friday night.  At 11:00 p.m. EDT on Friday the center of Subtropical Storm Oscar was located at latitude 26.7°N and longitude 45.7°W which put it about 1210 miles (1940 km) east-southeast of Bermuda.  Oscar was moving toward the north-northwest 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 gust to 60 m.p.h. (95 km/h).  The minimum surface temperature was 1005 mb.

More thunderstorms developed closer to the center of a low pressure system east-southeast of Bermuda on Friday night and the National Hurricane Center designated the system as Subtropical Storm Oscar.  The strongest winds were occurring in a band of showers and thunderstorms about 80 to 100 miles (130 to 160 km) east of the center of the low pressure system.  Several other bands were forming southeast of the center of circulation.  Bands in other parts of Subtropical Storm Oscar consisted primarily of showers and low clouds.

Subtropical Storm Oscar will move through an area somewhat favorable for intensification.  Oscar will move over water where the Sea Surface Temperature is near 27°C.  An upper level low will move just to the south of Subtropical Storm Oscar.  The upper level low will produce easterly winds which will blow toward the top of the subtropical storm.  Those winds will cause moderate vertical wind shear which will inhibit intensification on Saturday.  In a day or so Oscar will move northwest of the upper level low and the vertical wind shear will decrease.

The upper level low will steer Subtropical Storm Oscar toward the north-northwest on Saturday.  When Oscar moves farther way from the upper level low, it will move south of a ridge of high pressure over the Atlantic Ocean.  The ridge will steer Subtropical Storm Oscar toward the west on Sunday and into early next week.  On its anticipated track Subtropical Storm Oscar could be southeast of Bermuda by Monday night.

Leslie Strengthens Into a Hurricane East of Bermuda

Former Tropical Storm Leslie strengthened into a hurricane east of Bermuda on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Hurricane Leslie was located at latitude 29.5°N and longitude 56.8°W which put it about 510 miles (825 km) east-southeast of Bermuda.  Leslie was nearly stationary.  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (155 km/h).  The minimum surface pressure was 975 mb.

After being designated as a subtropical storm, Hurricane Leslie made a transition to an extratropical cyclone and then back to a subtropical storm.  Leslie eventually moved over warmer water and the structure changed to that of a tropical storm, which intensified slowly until it reached hurricane intensity earlier this morning.  It is gradually exhibiting the classical appearance and structure of a hurricane.

There is a circular eye at the center of circulation.  A nearly complete ring of thunderstorms surrounds the eye and the strongest winds are occurring in that ring of storms.  Several bands of showers and thunderstorms are revolving around the core of Hurricane Leslie.  Storms near the core are generating upper level divergence which is pumping mass away from the hurricane, which is causing the surface pressure to decrease.  Winds to hurricane force extend out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extend out about 230 miles (370 km) from the center.

Hurricane Leslie will remain in an environment favorable for intensification for another day or two.  Leslie will remain over water where the Sea Surface Temperature is near 27.5°C.  it will be in a region where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Leslie is likely to get a little stronger during the next day or so.  Leslie will move over cooler water later this week and it will start to weaken when that happens.

Hurricane Leslie has been in an area where the steering winds were weak which is why it has meandered east of Bermuda during the past few days.  A subtropical ridge southeast of Leslie will strengthen during the next day or two and the ridge will start to steer the hurricane toward the north.  On its anticipated track Hurricane Leslie will move farther away from Bermuda later this week.

Florence Strengthens Back Into a Hurricane

Florence strengthened back into a hurricane on Sunday morning.  At 11:00 a.m. EDT on Sunday the center of Hurricane Florence was located at latitude 24.4°N and longitude 56.3°W which put it about 750 miles (1210 km) southeast of Bermuda.  Florence was moving toward the west at 6 m.p.h. (10 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 984 mb.

Hurricane Florence was better organized on Sunday morning.  A NOAA research aircraft reported a circular eye with a diameter of 24 miles (39 km).  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Florence.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.  Winds to hurricane force extended out about 20 miles (35 km) to the east of the center of circulation.  Winds to tropical storm force extended out about 115 miles (185 km) to the north of the center and about 50 miles (80 km) to the south of the center.

Hurricane Florence will be moving through an environment favorable for intensification.  Florence will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Florence will strengthen and it could intensify rapidly at times.  Florence is likely to be a major hurricane on Monday.

Hurricane Florence will move around the western end of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Florence in a general west-northwesterly direction.  On its anticipated track the center of Hurricane Florence will approach the southeast coast of the U.S. on Thursday.  It is likely to be a major hurricane at that time.

Elsewhere, Tropical Storm Helene and Tropical Storm Isaac moved westward over the tropical Atlantic Ocean.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Helene was located at latitude 13.2°N and longitude 25.0°W which put it about 120 miles (195 km) south-southwest of the Cabo Verde Islands.  Helene was moving toward the west at 13 m.p.h. (20 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 997 mb.  Tropical Storm Warnings were in effect for Santiago, Fogo and Brava.

At 11:00 a.m. EDT on Sunday the center of Tropical Storm Isaac was located at latitude 14.3°N and longitude 39.1°W which put it about 1470 miles (2370 km) east of the Windward Islands.  Isaac was moving toward the west at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 65 m.p.h. (105km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 999 mb.

Tropical Storm Florence Reorganizes Southeast of Bermuda

Tropical Storm Florence reorganized southeast of Bermuda on Saturday.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Florence was located at latitude 24.6°N and longitude 55.2°W which put it about 790 miles (1270 km) southeast of Bermuda.  Florence was moving toward the west at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 989 mb.

Vertical wind shear decreased around Tropical Storm Florence and the circulation showed evidence of better organization.  Stronger thunderstorms developed near the center of circulation and a primary rainband wrapped about three quarters of the way around the center.  An eye appeared to be forming.  Thunderstorms near the center generated more upper level divergence which pumped away mass and the surface pressure decreased on Saturday.  More thunderstorms also developed in other rainbands that were revolving around the core of the circulation.  Tropical Storm Florence appeared to be on the threshold of regaining hurricane intensity.

Tropical Storm Florence will be moving through an environment favorable for intensification during the next two or three days.  Florence will move over water where the Sea Surface Temperature is near 29°C.  It will move into a region where the upper level winds are weaker and there will be less vertical wind shear.  Tropical Storm Florence will intensify back into a hurricane on Sunday.  It could intensify rapidly once a eye and complete eyewall form.  Florence is likely to become a major hurricane by early next week.

Tropical Storm Florence will move near the western end of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Florence in a general west-northwesterly direction during the next few days.  On its anticipated track Florence could approach the southeast coast of the U.S. by Thursday.  It is likely to be a major hurricane at that time.  The steering currents could weaken when Florence approaches the U.S. and it is too early to make a precise forecast of landfall.

Elsewhere, Tropical Storms Helene and Isaac strengthened over the eastern tropical Atlantic Ocean.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Helene was located at latitude 13.2°N and longitude 22.8°W which put it about 155 miles (250 km) southeast of the Cabo Verde Islands.  Helene was moving toward the west 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. (120km/h).  The minimum surface pressure was 999 mb.  Tropical Storm Warnings were in effect for Santiago, Fogo and Brava.

At 11:00 p.m. EDT the center of Tropical Storm Isaac was located at latitude 14.4°N and longitude 37.5°W which put it about 1580 miles (2540 km) east of the Windward Islands.  Isaac was moving toward the west at 8 m.p.h. (13 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.

Florence Weakens to a Tropical Storm

Former Hurricane Florence weakened to a tropical storm on Thursday.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Florence was located at latitude 25.1°N and longitude 49.8°W which put it about 1035 miles (1665 km) east-southeast of Bermuda.  Florence was moving toward the west-northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 993 mb.

An upper level trough west of former Hurricane Florence produced strong southwesterly winds which blew across the top of the circulation.  Those winds caused strong vertical wind shear and Florence weakened into a tropical storm.  Thunderstorms dissipated in rainbands in the western half of the tropical storm.  The ring of thunderstorms around the eye weakened and the western side of the eyewall was disrupted.  However, a distinct low level center of circulation persisted.  Thunderstorms northeast of the center still generated upper level divergence which pumped mass away to the northeast.

Tropical Storm Florence could weaken further on Friday because it will still be in the area of strong vertical wind shear.  However, as long as the lower part of the circulation remains intact, Tropical Storm Florence will be likely to strengthen during the weekend.  Florence is currently over water where the Sea Surface Temperature is near 28°C.  It will move over even warmer water during the weekend.  When Florence moves farther west, it will move into an area where the upper level winds are weaker and the wind shear will decrease.  Tropical Storm Florence is likely to intensify back into a hurricane during the weekend.

Tropical Storm Florence will move south of the subtropical high over the Atlantic Ocean.  The high will steer Florence in a generally west-northwesterly direction.  On its anticipated track, Florence could be southeast of Bermuda by Monday.  Florence could approach the east coast of the U.S. later next week.

Florence Strengthens Into a Major Hurricane

Hurricane Florence strengthened rapidly into a major hurricane on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Hurricane Florence was located at latitude 22.0°N and longitude 45.7°W which put it about 1370 miles (2205 km) east-southeast of Bermuda.  Florence was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 145 m.p.h. (235 km/h).  The minimum surface pressure was 957 mb.

Hurricane Florence strengthened rapidly on Wednesday morning.  A small circular eye formed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Florence.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.

The circulation of Hurricane Florence is small.  Winds to hurricane force extend out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extend out about 95 miles (155 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Florence is 23.6.  The Hurricane Size Index (HSI) is 7.0 and the Hurricane Wind Intensity Size Index (HWISI) is 30.6.

Hurricane Florence will move through an environment capable of supporting a strong hurricane.  Florence is currently over water where the Sea Surface Temperature is near 27°C and it will move over warmer water during the next several days.  An upper level trough north of Florence is producing westerly winds which are blowing toward the top of the hurricane.  However, those winds do not seem to be creating significant vertical wind shear.  Hurricane Florence could maintain its intensity and there is a chance it could get stronger when it moves over warmer water.  Because of the small circulation, if there are changes in the environment around Hurricane Florence, then the intensity could change quickly.  Also, any eyewall replacement cycles could cause the intensity to fluctuate.

Hurricane Florence will move south of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Florence in a general northwesterly direction during the next few days.  On its anticipated track Hurricane Norman could be southeast of Bermuda by early next week.  The guidance from the numerical models has been variable and there is still much uncertainty about the track Hurricane Florence will take later next week.

Elsewhere, Tropical Depression Gordon was dropping rain on Alabama and Mississippi.  At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Gordon was located at latitude 32.3°N and longitude 90.2°W which put it about 5 miles (10 km) west of Jackson, Mississippi.  Gordon was moving toward the northwest at 14 m.p.h. (22 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 1008 mb.