Tag Archives: Bermuda

Tropical Storm Gordon Nears Gulf Coast

Tropical Storm Gordon moved closer to the Gulf Coast of the U.S. on Tuesday morning.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Gordon was located at latitude 28.5°N and longitude 86.8°W which put it about 145 miles (235 km) east-southeast of the mouth of the Mississippi River.  Gordon was moving toward the northwest at 15 m.p.h. (24 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 1001 mb.

A Hurricane Warning was in effect for the portion of the coast from the mouth of the Pearl River to the Alabama-Florida border.  Tropical Storm Warnings were in effect for the portions of the coast from Grand Isle, Louisiana to the mouth of the Pearl River including Lake Pontchartrain and from the Alabama-Florida border to the Okaloosa-Walton County line in Florida.

The circulation of Tropical Storm Gordon appeared to be getting more organized on Tuesday morning.  More thunderstorms developed near the center of circulation.  Storms near the center were generating upper level divergence which was pumping mass away to the east of the tropical storm.  Several bands of showers and thunderstorms north and east of the center were moving toward the Gulf Coast.  The bands southwest of the center consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out about 80 miles (130 km) from the center of circulation, but the winds were weaker in the southwestern quadrant of Tropical Storm Gordon.

Tropical Storm Gordon could strengthen into a hurricane before it makes landfall.  Gordon will move over water where the Sea Surface Temperature is near 30°C.  An upper level trough over the southeastern U.S. was producing southwesterly winds which were blowing toward the top of the circulation.  Those winds were causing some vertical shear, but they will not be strong enough to prevent intensification.  The surface pressure decreased slightly on Tuesday morning.  Increased friction near the coast could cause the circulation to tighten around the center, when Tropical Storm Gordon gets closer to the Gulf Coast.

Tropical Storm Gordon will move around the southwestern end of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Gordon in a general northwesterly direction during the next several days.  On its anticipated track the center of Hurricane Gordon is likely to make landfall on the northern Gulf Coast on Tuesday night.  Gordon will produce winds to near hurricane force at the coast.  It could cause a storm surge of 5 to 8 feet (1.5 to 2.5 meters) east of the center where the wind blows water toward the coast.  The highest storm surge will occur in bays and the mouths of streams and rivers where the shape of the coast funnels water into those areas.  Tropical Storm Gordon will also drop heavy rain over portions of northwest Florida, southwest Alabama, Mississippi and eastern Louisiana.  Locally heavy rain could create the potential for flash floods.

Elsewhere over the Atlantic Ocean, former Tropical Storm Florence strengthened into the third Atlantic hurricane of 2018.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Florence was located at latitude 19.7°N and longitude 42.5°W which put it about 1270 miles (2045 km) east-northeast of the Lesser Antilles.  Florence was moving toward the west-northwest at 12 m.p.h. (19 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 990 mb.

Potential Tropical Cyclone Seven Causes Tropical Storm Watch for U.S. Gulf Coast

Potential Tropical Cyclone Seven caused the National Hurricane Center to issue a Tropical Storm Watch for a portion of the U.S. Gulf Coast on Sunday afternoon.  A Tropical Storm Watch was in effect for the portion of the coast from the Alabama-Florida border to Morgan City, Louisiana including Lake Pontchartrain.  At 5:00 p.m. EDT on Sunday the center of Potential Tropical Cyclone Seven was located at latitude 22.7°N and longitude 77.3°W which put it about 275 miles (445 km) east-southeast of Marathon, Florida.  It was moving toward the west-northwest at 15 m.p.h (24 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 1012 mb.

Bands of showers and thunderstorms began to form in a tropical wave over the Bahamas and the National Hurricane Center designated the system as Potential Tropical Cyclone Seven in order to be able to issue the Tropical Storm Watch for the north coast of the Gulf of Mexico.  The circulation of Potential Tropical Cyclone Seven was still organizing.  A distinct low level center of circulation had not formed.  Bands of showers and thunderstorms were developing and the bands were starting to revolve around the inner part of the weather system.  Thunderstorms were beginning to generate some upper level divergence.

Potential Tropical Cyclone Seven will be moving into an environment favorable for intensification.  It will move over water where the Sea Surface Temperature is near 30°C.  An upper level ridge is forecast to develop over Potential Tropical Cyclone Seven.  If that occurs, then the upper level winds would be weak and there would be little vertical wind shear.  Potential Tropical Cyclone Seven is forecast to intensify into Tropical Storm Gordon.  If the system moves slowly enough, there is a chance it could strengthen into a hurricane before it reaches the Gulf Coast.

Potential Tropical Cyclone Seven will move around the western end of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Potential Tropical Cyclone Seven in a general west-northwesterly direction.  On its anticipated track the system will move over the Florida Keys on Monday.  It will be over the eastern Gulf of Mexico on Tuesday and the system could reach the northern Gulf Coast late on Tuesday or early on Wednesday.

Elsewhere over the tropical Atlantic, Tropical Storm Florence was moving quickly away from the Cabo Verde Islands.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Florence was located at latitude 17.4°N and longitude 34.6°W which put it about 700 miles (1125 km) west of the Cabo Verde Islands.  Florence was moving toward the west-northwest at 15 m.p.h. (24 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 1000 mb.

Tropical Storm Florence Develops West of Cabo Verde Islands

Tropical Storm Florence developed west of the Cabo Verde Islands on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Florence was located at latitude 15.6°N and longitude 29.0°W which put it about 310 miles (500 km) west of the Cabo Verde Islands.  Florence 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 1002 mb.

The circulation of former Tropical Depression Six became better organized on Saturday and the National Hurricane Center designated the system as Tropical Storm Florence.  The center of circulation became more well defined and more thunderstorms developed closer to the center.  Numerous bands of showers and thunderstorms began to form.  The forming rainbands were revolving around the center of circulation.  Storms near the center started to generate upper level divergence.

Tropical Storm Florence will be moving through an environment somewhat favorable for intensification during the next day or two.  Florence will move over water where the Sea Surface Temperature is near 26°C.  It will move through a region where the upper level winds will be weak and there will be little vertical wind shear.  Tropical Storm Florence is likely to intensify during the next 24 to 48 hours.

Tropical Storm Florence will be moving south of a subtropical ridge over the eastern Atlantic Ocean.  The ridge will steer Florence in a general west-northwesterly motion during the next two or three days.  On its anticipated track the center of Tropical Storm Florence will move farther away from the Cabo Verde Islands.

Beryl Reorganizes as a Subtropical Storm North of Bermuda

A low pressure system associated with former Tropical Storm Beryl reorganized north of Bermuda on Saturday and the National Hurricane Center designated the system as Subtropical Storm Beryl.  At 2:00 p.m. EDT on Saturday the center of Subtropical Storm Beryl was located at latitude 36.4°N and longitude 65.7°W which put it about 575 miles (930 km) south-southwest of Halifax, Nova Scotia.  Beryl was moving toward the northeast 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 1010 mb.

The remnants of former Tropical Storm Beryl moved slowly across the northern Caribbean Sea and then over the southeastern Bahamas to a position northwest of Bermuda.  A low pressure system formed at the surface.  Bands of showers and thunderstorms developed and began to revolve around the the low pressure system.  The low pressure system moved under the eastern side of an upper level trough.  The trough contains colder air in the upper levels and it was also producing southwesterly winds which were blowing toward the top of the surface low pressure system.  The southwesterly winds were generating moderate vertical wind shear and the strongest rainbands were occurring on the eastern side of the surface low.  Some drier air was moving around the western and southern part of the upper level trough, which may have contributed to the weaker bands on the western side of the circulation.  The presence of the upper level trough and the asymmetrical distribution of thunderstorms around the surface low prompted the National Hurricane Center to designate the system as a subtropical storm.

Subtropical Storm Beryl will move through an environment marginally favorable for intensification during the next 24 hours.  Beryl will move over water where the Sea Surface Temperature is near 26°C.  The upper level trough will continue to produce moderate vertical wind shear.  The wind shear and the drier air will inhibit intensification.  Subtropical Storm Beryl could intensify a little more during the next 24 hours.  Beryl will move over colder water later on Sunday and it will start to weaken when that occurs.

The upper level trough was steering Subtropical Storm Beryl toward the northeast and a general motion in that direction is forecast to continue for several more days.  On its anticipated track Subtropical Storm Beryl will pass south of Nova Scotia on Sunday.  Beryl could be near Newfoundland by Tuesday.

Chris Strengthens to a Hurricane Southeast of Cape Hatteras

Former Tropical Storm Chris strengthened to a hurricane southeast of Cape Hatteras on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Hurricane Chris was located at latitude 33.7°N and longitude 72.4°W which put it about 205 miles (330 km) east-southeast of Cape Hatteras, North Carolina.  Chris was moving toward the northeast 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 980 mb.

Hurricane Chris strengthened on Tuesday when it moved northeast of cooler water Chris had mixed to the surface while it was meandering off the coast of the Carolinas.  An eye with a diameter of 30 miles (50 km) formed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in the eastern side of that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Hurricane Chris.  The strongest rainbands were in the eastern half of the circulation.  Drier air near the western half of the circulation was contributing to the weaker bands in that part of the hurricane.  Storms in the core of the circulation were generating upper level divergence which was pumping mass away to the north and east of the hurricane.  Winds to hurricane force extended out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extended out about 95 miles (155 km) from the center.

Hurricane Chris will move through an environment favorable for intensification on Wednesday.  Chris will move over water where the Sea Surface Temperature is near 28°C.  An upper level trough over the northeastern U.S. will produce southwesterly winds that will blow toward the top of the hurricane.  The winds speeds are similar at most levels and they will not generate a lot of vertical wind shear during the next 24 hours.  Hurricane Chris will strengthen on Wednesday and it could intensify rapidly.  Chris will move over cooler water when it gets north of the Gulf Stream and it will start to weaken when that occurs.

The trough over the northeastern U.S. will steer Hurricane Chris toward the northeast.  On its anticipated track Chris will move away from the coast of North Carolina.  Chris could be south of Nova Scotia in about 36 hours and it could be near Newfoundland in several days.

Elsewhere, the remnants of former Tropical Storm Beryl crossed Hispaniola and they were moving toward the southeastern Bahamas.  At 2:00 p.m. EDT on Tuesday the center of Former Tropical Storm Chris was located at latitude 20.1°N and longitude 72.6°W which put it about 40 miles (65 km) northeast of Port de Paix, Haiti.  It was moving toward the northwest at 17 m.p.h. (28 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 1013 mb.  A reconnaissance aircraft is scheduled to investigate the system on Wednesday if there are signs that it could be reorganizing into a tropical cyclone.

Tropical Storm Chris Develops South of Cape Hatteras, Beryl Nears Lesser Antilles

Tropical Storm Chris developed south of Cape Hatteras on Sunday morning, while Tropical Storm Beryl neared the Lesser Antilles.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Chris was located at latitude 32.9°N and longitude 75.0°W which put it about 160 miles (260 km) south of Cape Hatteras, North Carolina.  Chris was nearly stationary.  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 1006 mb.

Thunderstorms developed closer to the center of circulation on Sunday morning and the National Hurricane Center designated former Tropical Depression Three as Tropical Storm Chris.  The circulation of Chris was organizing quickly.  A band of showers and thunderstorms was wrapping around the center of circulation.  Several other rainbands were revolving around the core of the tropical storm.  The bands northwest of the center were weaker because there was drier air in that part of Chris.  The storms near the center of circulation were beginning to generate upper level divergence.

Tropical Storm Chris will remain in an environment favorable for intensification for the next two or three days.  The water in the upper portion of the Atlantic Ocean east of the Carolinas is warmer than normal.  Tropical Storm Chris will be over water where the Sea Surface Temperature is near 28°C.  Chris will be southeast of an upper level trough over the northeastern quarter of the U.S. and it will be under a small upper level ridge.  The upper level winds will be weak and there will be little vertical wind shear.  Tropical Storm Chris will continue to intensify and it could strengthen to a hurricane in the next day or two.

Since Tropical Storm Chris is under the small upper level ridge, the steering winds are weak.  Chris may not move much during the next 24 to 48 hours.  Tropical Storm Chris is forecast to linger of the coast of the Carolinas for several days.  Eventually an upper level trough will approach from the west and start to push Chris toward the northeast.

Elsewhere, Tropical Storm Beryl was nearing the Lesser Antilles on Sunday morning.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Beryl was located at latitude 14.4°N and longitude 57.9°W which put it about 210 miles (335 km) east of Martinique.  Beryl was moving toward the west-northwest at 23 m.p.h. (37 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 1007 mb.

Tropical Storm Warnings were in effect for Dominica and Guadeloupe.  Tropical Storm Watches were in effect for Saba, St. Eustatius, St. Maarten, St. Martin, Martinique, St. Lucia, and St. Barthelemy.

Thunderstorms continued to develop near the center of Tropical Storm Beryl on Sunday morning and the weakening trend halted at least temporarily.  Beryl remained a small tropical storm.  Winds to tropical storm force only extended out about 45 miles (75 km) from the center of circulation.  There were several bands of showers and thunderstorms in the eastern half of Tropical Storm Beryl.  The bands in the western half of the circulation consisted primarily of showers and low clouds.

Tropical Storm Beryl is forecast to into a region where the easterly winds in the lower levels are stronger.  That would increase the vertical wind shear and make it difficult for the circulation to stay vertically coherent.  Beryl will move over water where the Sea Surface Temperature is near 27°C.  So, there will be enough energy in the upper ocean to support a tropical storm if the wind shear is not too strong.  Tropical Storm Beryl is forecast to weaken when it moves over the eastern Caribbean Sea, but that will depend on how strong the vertical shear gets.

Tropical Storm Beryl is moving south of the subtropical high over the Atlantic Ocean which is steering Beryl toward the west-northwest.  A general motion toward the west-northwest is forecast to continue for several more days.  On its anticipated track Tropical Storm Beryl will bring gusty winds and locally heavy rain to St. Lucia, Martinique, Dominica and Guadeloupe during the next few hours,

Tropical Storm Beryl Weakens East of the Lesser Antilles

Tropical Storm Beryl weakened on Saturday as it move closer to the Lesser Antilles.  At 11:00 p.m. EDT on Saturday the center of circulation was located at latitude 13.1°N and longitude 54.3°W which put it about 495 miles (795 km) east-southeast of the Lesser Antilles.  Beryl was moving toward the west-northwest at 18 m.p.h. (30 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.

Tropical Storm Warnings were in effect for Dominica and Guadeloupe.  Tropical Storm Watches were in effect for Saba, St. Eustatius, St. Maarten, Martinique, St. Martin, St. Barthelemy, Barbados and St. Lucia.

Tropical Storm Beryl moved into a region where the easterly winds in the lower level were stronger and the increased vertical wind shear started to blow the lower part of the circulation to the west of the upper part of Beryl.  It also seemed to move into an area of drier air, which caused most of the stronger thunderstorms to weaken.  There was still a well organized circulation in the lower levels, but it weakened on Saturday.  More thunderstorms developed near the center of circulation and on the eastern side of Tropical Storm Beryl in recent hours.  If those storms persist then Beryl could strengthen again, but if they dissipate quickly, then the tropical storm could weaken again on Sunday.

Tropical Storm Beryl will move through an environment that contains factors that are favorable for intensification and other factors that are unfavorable.  Beryl will move over water where the Sea Surface Temperature is near 27°C.  It will move through an area where the lower level winds are stronger and so there will be more vertical wind shear.  There will be areas of moister air within a larger area of drier air.  If the recently developed thunderstorms persist on Sunday, then the Beryl could strengthen again.  However, if the storms dissipate in a few hours, then Tropical Storm Beryl could weaken further.  The small size of the circulation means that rapid changes in intensity can occur.

Tropical Storm Beryl was moving south of the subtropical high over the Atlantic Ocean.  The high was steering Beryl toward the west-northwest and that general motion is forecast to continue for the next several days.  On its anticipated track Tropical Storm Beryl could reach the Lesser Antilles on Sunday night.  There is a lot of uncertainty about how strong Beryl may be when it reaches those islands.

Elsewhere over the Atlantic Ocean Tropical Depression Three spun south of Cape Hatteras.  At 11:00 p.m. EDT on Saturday the center of Tropical Depression Three was located at latitude 32.9°N and longitude 75.1°W which put it about 160 miles (260 km) south of Cape Hatteras, North Carolina.  It was nearly stationary.  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 1014 mb.

Hurricane Beryl Prompts Watches for Lesser Antilles, TD 3 Forms Southeast of Carolinas

The potential approach of Hurricane Beryl prompted the issuance of Watches for some of the Lesser Antilles on Friday afternoon, while at the same time Tropical Depression Three formed southeast of the Carolinas.  At 5:00 p.m. EDT on Friday the center of Hurricane Beryl was located at latitude 10.6°N and longitude 47.8°W which put it about 965 miles (1555 km) east-southeast of the Leeward Islands.  Beryl was moving toward the west at 15 m.p.h. (24 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. (155 km/h).  The minimum surface pressure was 994 mb.

A Hurricane Watch has been issued for Dominica.  Tropical Storm Watches have been issued for Martinique, Guadeloupe, St. Martin and St. Barthelemy.

The circulation of Hurricane Beryl remains very small.  The pinhole is no longer visible on satellite imagery, although strong thunderstorms continue to develop near the center of circulation.  Short narrow bands or showers and thunderstorms are revolving around the core of Hurricane Beryl.  Winds to hurricane force only extend out about 10 miles (15 km) from the center of circulation.  Winds to tropical storm force extend out about 40 miles (65 km) from the center.

Hurricane Beryl will move through an environment favorable for intensification during the next 24 hours.  Beryl will move over water where the Sea Surface Temperature is near 27°C.  It is moving south of an upper level ridge.  The ridge is producing easterly winds which are blowing toward the top of the circulation.  However, the wind speeds are similar at all levels and there is currently little vertical wind shear.  Tropical Storm Beryl could intensify on Saturday, but the circulation is so small that any increase in wind shear could cause rapid weakening.

The subtropical ridge over the Atlantic Ocean is north of Hurricane Beryl and the ridge has been steering Beryl toward the west.  A motion more toward the west-northwest is forecast during the weekend.  On its anticipated track Hurricane Beryl will approach the Lesser Antilles later on Sunday.  That is the reason why the Watches were issued for some of those islands.  Beryl could still be a hurricane when it gets to the Lesser Antilles, but there is a lot of uncertainty about the intensity forecast because the hurricane is so small.

Elsewhere over the Atlantic Ocean, the National Hurricane Center designated an area of low pressure southeast of the coast of the Carolinas as Tropical Depression Three.  At 5:00 p.m. EDT on Friday the center of Tropical Depression Three was located at latitude 32.2°N and longitude 73.8°W which put it about 230 miles (370 km) south-southeast of Cape Hatteras, North Carolina.  It was moving toward the north-northwest at 5 m.p.h. (8 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 1016 mb.  Tropical Depression Three is forecast to meander off the coast of the Carolinas during the weekend.  It could strengthen into a tropical storm and there is a chance it could intensify into a hurricane next week.

System to Bring Wind, Rain to Bahamas and South Florida

A complex weather system near the Bahamas is forecast to move westward and it will bring gusty winds and locally heavy rain to parts of the Bahamas and South Florida during the weekend.  The circulation is strongest in the middle and upper troposphere.  An upper level low is centered near the Bahamas.  Showers and thunderstorms are occurring north and east of the upper low.  There is not a distinct center of circulation in the lower troposphere or at the surface.  There is a small upper level ridge to the east of the upper low and the ridge is producing some upper level divergence which is pumping mass away to the east of the system.

The system will move through an environment that is only marginally favorable for the development of a tropical cyclone.  It will move over water where the Sea Surface Temperature is near 26°C.  So, there is potentially enough energy in the upper ocean to support the development of a minimal tropical cyclone.  The upper low and the ridge to the east are southerly winds near the Bahamas and westerly winds southeast of the Bahamas.  Those winds are causing strong vertical wind shear.  The winds are weaker near the center of the upper low, but there are no thunderstorms in that region at the current time.  If a surface low were to develop under the center of the upper low, then there would be the possibility of some slow development.  A second, possible scenario is that a subtropical cyclone develops north and east of the upper low where the showers and thunderstorms are forming.

The National Hurricane Center (NHC) issued a special Tropical Weather Outlook on this system at 10:45 a.m. EDT on Friday.  NHC indicated that “no significant development” is expected and it gives a 0% probability of the formation of a tropical cyclone.

The upper level low is forecast to move south-southwest over the northwestern Caribbean Sea during the next 72 hours.  The surface and lower parts of the system are forecast to move across the Bahamas toward South Florida during the weekend.  Since the showers and thunderstorms are occurring north and east of the upper low, this could bring gusty winds and locally heavy rain to parts of the Bahamas and South Florida during the weekend.  Some of the humid air on the northeastern periphery of the system could be pulled toward the Carolinas ahead of an approaching cold front.  The moist air could enhance rainfall in eastern South Carolina and eastern North Carolina when the cold front moves through those places and lifts the air.

Tropical Depression 19 Strengthens to Tropical Storm Rina

Tropical Depression Nineteen strengthened into Tropical Storm Rina on Monday night.  At 10:00 p.m. EST on Monday the center of Tropical Storm Rina was located at latitude 30.4°N and longitude 49.9°W which put it about 890 miles (1430 km) east of Bermuda.  Rina was moving toward the north at 7 m.p.h. (11 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.

Although an upper level low northwest of Tropical Depression Nineteen continued to produce westerly winds which caused moderate vertical wind shear, stronger thunderstorms developed east of the center of circulation.  Downdrafts in those storms were able to transport stronger winds to the surface and winds to tropical storm force were occurring at the surface.  The National Hurricane Center upgraded Tropical Depression Nineteen to Tropical Storm Rina on Monday night.

The circulation of Tropical Storm Rina is asymmetrical.  The stronger storms are occurring east of the center of circulation.  The winds to tropical storm force are occurring northeast of the center.  Winds to tropical storm force extend out about 60 miles to the northeast of the center of circulation.  The bands west of the center consist primarily of lower clouds and showers.  The upper level westerly winds are tilting the circulation toward the east with height.

The moderate vertical wind shear will continue to inhibit the intensification of Tropical Storm Rina.  Rina will move over water where the Sea Surface Temperature is near 25°C.  Although the water is cooler than it is in the tropical, colder air in the upper levels will make the atmosphere unstable enough to allow thunderstorms to continue to develop.  The vertical wind shear could decrease during the next 24 to 36 hours and some intensification is possible.  When Tropical Storm Rina moves farther north, it will move over colder water.

The upper level low to the northwest of Tropical Storm Rina and a ridge to the east of Rina are steering the tropical storm toward the north.  A general motion is expected to continue for another day or two.  On its anticipated track Tropical Storm Rina will pass between Labrador and the Azores.