Tag Archives: Halifax

Tropical Cyclone Development Unlikely

The National Hurricane Center indicated on Monday that a strong extratropical cyclone over the Atlantic Ocean south of Nova Scotia is unlikely to make a transition to a tropical cyclone. At 1:00 p.m. EST on Monday the center of the extratropical cyclone was located at latitude 37.8°N and longitude 63.8°W which put it about 460 miles (745 km) south of Halifax, Nova Scotia. The extratropical cyclone was moving toward the north-northeast at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 986 mb.

The National Hurricane Center (NHC) issued a special Tropical Weather Outlook on Monday morning for a strong extratropical cyclone over the Atlantic Ocean south of Nova Scotia. NHC indicated in the Tropical Weather Outlook that it was unlikely the extratropical cyclone would make a transition to a tropical cyclone or a subtropical cyclone. The extratropical cyclone was subsequently designated at Invest 90L.

A circular area of showers and thunderstorms developed at the center of a large, occluded extratropical cyclone south of Nova Scotia on Monday. A clear circular area was visible at the center of the area of showers and thunderstorms on satellite images. The clear area resembled the appearance of an eye in a tropical cyclone. The thunderstorms did not extend high into the troposphere because the center of the extratropical cyclone was over water where the Sea Surface Temperatures are near 20˚C. The circular area of showers and thunderstorms in the middle of the extratropical cyclone was surrounded by a large area of cold, dry air. Bands of low clouds and showers were occurring in the cold, dry air. The extratropical cyclone was producing a large area of winds to tropical storm force.

The extratropical cyclone will move through an area that is only marginally favorable for a transition to a subtropical cyclone or a tropical cyclone. The extratropical cyclone will move over over water where the Sea Surface Temperatures are colder than 20˚C. It will move under the eastern part of an upper level low south of Nova Scotia. The upper level low will produce southerly winds that will blow toward the top of the extatropical cyclone. However, the upper level low is almost stacked vertically with the surface low pressure systems. So, the winds at different levels of the atmosphere are similar and there will be little vertical wind shear. Cold, dry air will continue to surrounded the circular area of thunderstorms at the center of the extratropical cyclone. Cold Sea Surface Temperatures and cold, dry air around the area of thunderstorms will inhibit a transition to a subtropical cyclone. There is a slight chance the extratropical cyclone could make a transition to a subtropical cyclone during the next 24 hours before it moves over even colder water.

The upper level low will steer the extratropical cyclone toward the north during the next 24 hours. On its anticipated track the extratropical cyclone could reach Nova Scotia on Tuesday. It will bring gusty winds and locally heavy rain to Nova Scotia.

Hurricane Fiona Nears Canadian Maritimes

Hurricane Fiona neared the Canadian Maritimes on Friday night. At 11:00 p.m. EDT on Friday the center of Hurricane Fiona was located at latitude 44.5°N and longitude 60.8°W which put it about 140 miles (220 km) east of Halifax, Nova Scotia. Fiona was moving toward the north at 46 m.p.h. (74 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 933 mb.

A Hurricane Warning was in effect for the portion of the coast from Hubbards to Brule, Nova Scotia. Hurricane Warnings were in effect for Prince Edward Islands and Isle de la Madeline. A Hurricane Warning was in effect for the portion of the coast from Parson’s Pond to Francois, Newfoundland. A Tropical Storm Warning was in effect for St. Andrews, New Brunswick to Hubbards, Nova Scotia. A Tropical Storm Warning was in effect for the portion of the coast from Brule, Nova Scotia to Cap Madeline, Quebec. Tropical Storm Warnings were in effect for Anticosti Island and for the portion of the coast from Sheldrake, Quebec to Parson’s Pond, Newfoundland. A Tropical Storm Warning was in effect for the portion of the coast from Boat Harbor to Hare Bay, Newfoundland. A Tropical Storm Warning was in effect for the portion of the coast from Francois to St. Lawrence, Newfoundland. A Tropical Storm Watch was in effect for the portion of the coast from Boat Harbor, Newfoundland to West Bay, Labrador.

Hurricane Fiona was making a rapid transition to a large, powerful extratropical cyclone on Friday night. The former eye and eyewall were no longer present at the center of Fiona. Most of the remaining thunderstorms were in bands northeast of the center of Fiona’s circulation. Cooler drier air was wrapping around the western and southern sides of the circulation. Upper level divergence above Hurricane Fiona was still pumping mass away and the surface pressure remained around 933 mb.

Hurricane Fiona grew much larger during the transition to an extratropical cyclone. Winds to hurricane force extended out 185 miles (295 km) from the center of Fiona’s circulation. Winds to tropical storm force extended out 345 miles (555 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Fiona was 17.8. The Hurricane Size Index (HSI) was 48.4 and the Hurricane Wind Intensity Size Index (HWISI) was 66.2. Hurricane Fiona was capable of causing extensive serious damage.

An upper level trough over eastern Canada will steer Hurricane Fiona quickly toward the north during the weekend. The strongest winds will occur over eastern Nova Scotia and western Newfoundland. Strong winds will also affect the rest of Nova Scotia and Newfoundland, Prince Edward Island, parts of New Brunswick, Quebec and Labrador. The large circulation around Hurricane Fiona could cause widespread electrical outages. Locally heavy rain could cause floods in some places. Large waves and a storm surge could cause damage along the coast.

Elsewhere over the Atlantic Ocean, Tropical Storm Gaston brought wind and rain to the Azores, Tropical Storm Hermine moved northeast of the Cabo Verde Islands and Tropical Storm Ian formed over the Caribbean Sea.

At 11:00 p.m. EDT on Friday the center of Tropical Storm Gaston was located at latitude 38.9°N and longitude 29.5°W which put it about 50 miles (80 km) west-northwest of the Faial, Azores. Gaston was moving toward the southwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 999 mb.

Tropical Storm Warnings were in effect for Corvo, Flores, Faial, Pico, Sao Jorge, Graciosa, and Terceira.

At 11:00 p.m. EDT on Friday the center of Tropical Storm Hermine was located at latitude 19.4°N and longitude 20.8°W which put it about 315 miles (505 km) northeast of the Cabo Verde Islands. Hermine was moving toward the north at 10 m.p.h. (16 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 1002 mb.

At 11:00 p.m. EDT on Friday the center of Tropical Storm Ian was located at latitude 14.8°N and longitude 72.0°W which put it about 385 miles (625 km) southeast of Kingston, Jamaica. Ian was moving toward the west-northwest 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 1005 mb.

Hurricane Watches were in effect for the Cayman Islands including Grand Cayman, Little Cayman and Cayman Brac. A Tropical Storm Watch was in effect for Jamaica.

Tropical Depression 16 Forms East of Northern Leeward Islands

Tropical Depression Sixteen formed east of the Northern Leeward Islands on Saturday night. At 11:00 p.m. EDT on Saturday the center of Tropical Depression Sixteen was located at latitude 16.4°N and longitude 53.1°W which put it about 670 miles (1080 km) east of the Northern Leeward Islands. The tropical depression was moving toward the west-northwest at 15 m.p.h. (24 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.

More thunderstorms developed near the center of a low pressure system east of the Northern Leeward Islands on Saturday night and the National Hurricane Center designated the system as Tropical Depression Sixteen. Thunderstorms were also developing in bands in the eastern and northern parts of the tropical depression. Bands in the southern and western parts of the circulation consisted primarily of showers and lower clouds. Storms near the center of circulation generated upper level divergence that pumped mass away to the north of the tropical depression.

Tropical Depression Sixteen will move through an environment somewhat favorable for intensification during the next 24 hours. The depression will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western part of an upper level ridge. The ridge will produce southerly winds that will blow toward the top of the tropical depression. Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification. Tropical Depression Sixteen is likely to strengthen to a tropical storm on Sunday. The tropical depression will move closer to an upper level trough northeast of Puerto Rico on Monday. The upper level trough will produce strong southwesterly winds that will blow toward the top of the tropical depression. Those winds will cause moderate vertical wind shear, which is likely to weaken the tropical depression.

Tropical Depression Sixteen will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer the depression toward the west-northwest during the next 24 hours. On its anticipated track Tropical Depression Sixteen could be northeast of the Northern Leeward Islands by Monday morning.

Elsewhere over the Atlantic Ocean, Tropical Storm Odette made a transition to an extratropical cyclone south of Nova Scotia. At 5:00 p.m. EDT on Saturday the center of former Tropical Storm Odette was located at latitude 39.1°N and longitude 65.1°W which put it about 385 miles (625 km) south-southwest of Halifax, Nova Scotia. Odette was moving toward the east-northeast at 18 m.p.h. (29 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 1001 mb.

Hurricane Teddy Heads for Nova Scotia, Beta Reaches Texas

Hurricane Teddy headed for Nova Scotia on Monday night as Tropical Storm Beta reached the coast of Texas.  At 11:00 p.m. EDT on Monday the center of Hurricane Teddy was located at latitude 35.6°N and longitude 61.5°W which put it about 630 miles (1015 km) south of Halifax, Nova Scotia.  Teddy was moving toward the north at 25 m.p.h. (41 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 956 mb.

A Tropical Storm Warning was in effect for the south coast of Nova Scotia from Digby to Meat Cove.  Tropical Storm Watches were in effect for the portions of the coast from Meat Cove to Tidnish and from Digby to Fort Lawrence.  Tropical Storm Watches were also in effect for Prince Edward Island, the Magdalen Islands and from Port aux Basques to Francois, Newfoundland.

The circulation around Hurricane Teddy expanded as it began a transition to an extratropical cyclone.  Winds to hurricane force extended out 100 miles (160 km) from the center of Teddy.  Winds to tropical storm force extended out 275 miles (445 km) from the center.  Drier air was wrapping around the southern side of Hurricane Teddy.  The strongest thunderstorms were in bands in the northern half of the hurricane.  Bands in the southern half of the circulation consisted primarily of showers and lower clouds.

An upper level trough over eastern North America will cause strong southerly winds which will blow toward the top of Hurricane Teddy.  Those winds will cause strong vertical wind shear and they will contribute to the extratropical transition of Teddy.  Hurricane Teddy will move over much cooler water when it approaches Nova Scotia.  Teddy will transform into a strong extratropical cyclone.

Hurricane Teddy will be steered rapidly toward the north by the upper level trough over eastern North America.  On its anticipated track Hurricane Teddy will approach Nova Scotia on Tuesday night.  Teddy will bring strong winds and heavy rain to Nova Scotia and southwestern Newfoundland.

Elsewhere, slow moving Tropical Storm Beta reached the coast of Texas on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Beta was located at latitude 28.4°N and longitude 96.3°W which put it about 5 miles (10 km) east of Port O Connor, Texas.  Beta was moving toward the northwest at 3 m.p.h. (5 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 999 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Port Aransas, Texas to Morgan City Louisiana.

Tropical Storm Beta weakened gradually on Monday as it moved slowly toward the coast of Texas.  Drier air continued to get pulled into the circulation which limited the development of new thunderstorms.  Without updrafts and downdrafts to transport momentum vertically, the circulation around Beta slowly spun down.

Even though Tropical Storm Beta weakened on Monday, its winds pushed water toward the coast of Texas.  Water levels rose along the coast and there were some reports of damage.  Waves contributed to beach erosion.  Moderate rain was falling over the region between Houston and Victoria, Texas.  The rain could cause flooding in some locations.

Tropical Storm Beta was forecast to move slowly toward the northeast along the coast of Texas during the next 24 to 36 hours.  Beta will continue to weaken, but winds will blow water toward the coast from several more days.  Locally heavy rain will continue to create a risk of floods until Tropical Storm Beta moves away from the area.

Hurricane Dorian Brings Powerful Winds to Nova Scotia

Hurricane Dorian brought powerful winds to Nova Scotia on Saturday.  At 8:00 p.m. EDT on Saturday the center of Hurricane Dorian was located at latitude 45.0°N and longitude 67.9°W which put it about 45 miles (75 km) northeast of Halifax, Nova Scotia.  Dorian was moving toward the northeast at 30 m.p.h. (48 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 960 mb.

Hurricane Warnings were in effect for Lower East Pubnico to Brule, Nova Scotia and from Indian Harbour to Hawke’s Bay, Newfoundland. Hurricane Watches were in effect for Prince Edward Island and for the Magdalen Islands. Tropical Storm Warnings were issued for Prince Edward Island and from Avonport to Lower East Pubnico, Nova Scotia. A Tropical Storm Warning was in effect for New Brunswick from Fundy National Park to Shediac. A Tropical Storm Warning was issued for the portion of the coast from Indian Harbour to Stone’s Cove, Newfoundland. Tropical Storm Warnings were issued for the portions of the coast from Hawke’s Bay to Fogo Island and from Mutton Bay to Mary’s Harbour.

Hurricane Dorian maintained its intensity and increased in size on Saturday while it sped across the northwestern Atlantic Ocean to the Canadian Maritime provinces.  Winds to hurricane force extended out about 115 miles (185 km) on the southern side of Hurricane Dorian.  Winds to tropical storm force extended out about 300 miles (480 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 16.5.  The Hurricane Size Index (HSI) was 26.3 and the Hurricane Wind Intensity Size Index (HWISI) was 42.8.  Hurricane Dorian was capable of causing widespread serious damage.

There were reports of wind damage and widespread power outages around Nova Scotia even before the center of Hurricane reached that area.  The large circulation around Dorian brought tropical storm force winds to Nova Scotia a few hours before the center made landfall.  The center of Hurricane Dorian officially made landfall south of Halifax, Nova Scotia on Saturday evening.

Hurricane Dorian had almost completed a transition to a large powerful extratropical cyclone.  That transition contributed to the increase in size of the circulation.  The strongest part of Hurricane Dorian will move across Nova Scotia during the next few hours.  The winds are likely to cause additional damage on Saturday night.  Hurricane Dorian will race across Nova Scotia, Cape Breton Island and New Brunswick on Saturday night.  Dorian will move over Newfoundland and southeastern Labrador on Sunday.  Hurricane Dorian has the potential to cause serious damage in all of those locations.

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.

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.