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.
Hurricane Chris weakened slowly on Wednesday as it passed well south of Nova Scotia. At 11:00 p.m. EDT on Wednesday the center of Hurricane Chris was located at latitude 39.6°N and longitude 63.0°W. Chris was moving toward the northeast at 29 m.p.h. (46 km/h). The maximum sustained wind speed was 85 m.p.h. (140 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 980 mb.
Hurricane Chris exhibited the structure of a hurricane on Thursday, but the clouds did not rise quite as high because it was over slightly cooler water. There was still an eye at the center of circulation. Several bands of showers and thunderstorms were revolving around the core of the circulation. The rainbands were weaker in the southwestern part of the hurricane because some drier air was entering that part of the circulation. Storms in the core of the circulation were generating upper level divergence.
Hurricane Chris is likely to weaken again on Thursday. It will start to move over much cooler water where there is less energy in the upper ocean. In addition an upper level trough over the eastern U.S. will produce southwesterly winds which will blow toward the upper part of the hurricane. Those winds will cause strong vertical wind shear. The shear will undercut the upper level divergence and tilt the circulation toward the northeast with height. Hurricane Chris will start to make a transition to an extratropical cyclone when the effects of the cooler water and stronger shear begin to alter the structure of the hurricane.
The upper level trough was steering Hurricane Chris rapidly toward the northeast and that motion is expected to continue for several more days. On its anticipated track Hurricane Chris will be near Labrador on Thursday night. The extratropical cyclone that results from the transition of Hurricane Chris will be near Iceland during the weekend.
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.
Hurricane Gert intensified to Category 2 on the Saffir-Simpson Scale as it sped over the Gulf Stream south of Nova Scotia on Wednesday afternoon. At 5:00 p.m. EDT on Wednesday the center of Hurricane Gert was located at latitude 38.7°N and longitude 62.4°W which put it about 410 miles (665 km) south of Halifax, Nova Scotia. Gert was moving toward the northeast at 31 m.p.h. (50 km/h). The maximum sustained wind speed was 100 mp.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h). The minimum surface pressure was 970 mb.
Although Hurricane Gert is at a fairly high latitude, it has the classic structure of a Hurricane. There is a fairly small eye at the center of circulation. The eye is surround by a ring of strong thunderstorm and the strongest winds are occurring in this ring of thunderstorms. There are additional bands of showers and thunderstorms revolving around the core of the hurricane. The circulation is symmetrical and thunderstorms in the core are producing upper level divergence which is pumping away mass to the northeast of the hurricane. Winds to hurricane force extend out about 40 miles (65 km) primarily to the east of the center of circulation. Winds to tropical storm force extend out about 140 miles (225 km) from the center.
Hurricane Gert is moving over the Gulf Stream which means it is moving over water where the Sea Surface Temperature (SST) is near 28.5°C. An upper level trough west of Gert is producing southwesterly winds which are blowing toward the top of the hurricane. However, there is not much change of wind speed with height, which means that there is little vertical wind shear. The combination of the warm water of the Gulf Stream and little vertical shear, allowed Hurricane Gert to strengthen on Wednesday.
Hurricane Gert could intensify during the next few hours, but it will soon move into a much less favorable environment. Gert will soon move north of the Gulf Stream where the SSTs are much cooler. The upper level trough is moving closer to Hurricane Gert and the winds are the upper level are forecast to get stronger. When those winds increase, there will be much more vertical wind shear. Colder water and more wind shear will cause Hurricane Gert to weaken on Thursday. Gert could make a transition to an extratropical cyclone in colder environment of the North Atlantic.
Southwesterly winds in the upper level trough are steering Hurricane Gert quickly toward the northeast and that general motion is expected to continue. On its anticipated track, Hurricane Gert will move south of Labrador and Greenland.
Even as Hurricane Gert speeds away over the North Atlantic three new tropical waves over the tropical Atlantic have the potential to develop into tropical cyclones. A tropical wave about 800 miles (1290 km) east of the Lesser Antilles designated as Invest 91L showed signs of organization on Wednesday. A few more thunderstorms developed closed to the center of circulation. A reconnaissance plane is scheduled to investigate this system on Thursday. A little farther to the east another tropical wave designated Invest 92L was also showing evidence or more organization. A third tropical wave just west of Africa also has the potential to develop during the next few days.
An area of low pressure off the East Coast of the U.S. rapidly acquired tropical characteristics on Monday and it was classified as Tropical Storm Claudette by the National Hurricane Center. At 1:00 p.m. EDT on Monday the center of Tropical Storm Claudette was located at latitude 37.4°N and longitude 68.1°W which put it about 290 miles (465 km) south-southeast of Nantucket Island, Massachusetts and about 550 miles (885 km) south-southwest of Halifax, Nova Scotia. Claudette was moving toward the northeast at 15 m.p.h. (24 km/h). The maximum sustained wind speed as 50 m.p.h. (85 km/h) and there were gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1004 mb.
Claudette began as a small low pressure system along a nearly stationary frontal boundary off the East Coast of the U.S. Moderate wind shear kept the system looking non-tropical for much of the weekend. The wind shear decreased on Monday morning and as the low moved over the warmer water of the Gulf Stream, thunderstorms developed near the center of circulation. The stationary frontal boundary dissipated and the system took on a more tropical appearance. Latent energy released in thunderstorms near the center produced the development of a warm core and some banding developed in the eastern portion of the circulation. As a result of those changes, the system was classified as Tropical Storm Claudette.
Claudette could strengthen in the short term. It is still over the Gulf Stream and the upper level winds are not too strong. However, once the tropical storm moves north of latitude 40°N, it will move over cooler Sea Surface Temperatures. In addition, stronger upper level winds will increase the vertical wind shear in a day or two. Claudette could make a transition to an extratropical cyclone within 48 hours.
A combination of a trough approaching the eastern U.S, and a ridge over the Atlantic are expected to steer Claudette toward the northeast. On its anticipated track, Claudette could approach eastern Nova Scotia in about 24 hours and Labrador in 30 hours.