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Hurricane Karen (2001)
Encyclopedia
Hurricane Karen was a hurricane of non-tropical origin that formed in October of the 2001 Atlantic hurricane season
. It developed out of the interaction between a cold front and an upper level trough
on October 10 located to the south of Bermuda
, and quickly strengthened as an extratropical storm. The storm passed near Bermuda on October 12, producing hurricane-force winds on the island. It then organized, becoming a subtropical cyclone
on the 12th and a tropical cyclone
on the 13th. Karen strengthened to reach 80 mph (130 km/h) winds as a Category 1 hurricane on the Saffir-Simpson Hurricane Scale
, and after weakening over cooler waters, it made landfall on Nova Scotia
as a tropical storm. It quickly became extratropical.
On Bermuda, winds from the precursor extratropical storm produced moderate damage, primarily to power lines and marine interests. Over 2/3 of the island's power subscribers were left without power during the worst of the storm, and several boats sank or ran aground from the high winds. Damage on Bermuda totaled to over $1.4 million (2001 USD; $1.7 million 2008 USD). In Atlantic Canada, Tropical Storm Karen produced light winds and rain, but caused minimal damage.
on October 10. During that day, a strong upper-level trough
moved southeastward off the southeast coast of the United States
. Due to several factors, including upward motion and strong diffluence—the rate at which a fluid moves—the area became baroclinically unstable. This caused the interaction between the trough and the front to develop into an extratropical low about 345 miles (555 km) southeast of Bermuda on October 11. The low moved quickly northward, then northwestward, strengthening quickly due to the instability of the atmosphere. Late on the 11th, the system slowed, and the upper-level circulation became aligned with the low-level circulation. The extratropical storm began to develop tropical characteristics
late on the 11th, including surface temperatures warmer than the surrounding environment, and vertical wind characteristics of a tropical cyclone. Based on its organization, the system developed into Subtropical Storm One early on October 12 while located about 35 miles (55 km) south of Bermuda.
While passing to the south of Bermuda, the subtropical storm
maintained winds of 70 mph (110 km/h), with wind gusts on the island surpassing 100 mph (160 km/h). After becoming dissociated from the Westerlies
, the system turned northward, and began to develop convection over the center. In addition, the frontal characteristics of the subtropical storm continually weakened. On October 13, based on an Advanced Microwave Sounding Unit
observation that stated that a warm core was present throughout the system, the National Hurricane Center
designated the system as a tropical storm, and gave it the name Karen
. At this point, Karen was located 200 miles (320 km) north of Bermuda. Karen slowly strengthened over the warm waters of the Gulf Stream
, and the storm intensified to a hurricane later on October 13. Convection continued to develop, and organized into a ring around the eye
as Karen reached its peak intensity of 80 mph (130 km/h) on October 14 while located about 400 miles (640 km) south of Halifax, Nova Scotia
.
Karen quickly weakened as it moved over cooler waters, and late on October 14 it degenerated back into a tropical storm as it accelerated northward. Convection
gradually decreased, and Karen made landfall on southwestern Nova Scotia
with winds of 45 mph (70 km/h) on October 15. Karen retained its tropical characteristics during and after making landfall, based on a research flight out of Halifax intended to study the early stages of extratropical transition. The flight reported arced bands and a warm-core system transitioning into a more typical mid-latitude system. Under the influence of a mid-latitude system, the storm turned sharply to the northeast, and after losing the remaining of its convection it became extratropical shortly after landfall. Continuing northward, the remnant low quickly weakened, and dissipated as it was absorbed by a larger extratropical storm over the Gulf of Saint Lawrence
.
issued a gale and later a storm warning for the island
, expecting winds of 50 to 60 mph (60 to 95 km/h). Several radio interviews and television stations issued information on the expected storm. Many residents believed they were insufficiently warned, though it is acknowledged that emergency managers and citizens pay less attention to gale warnings then they do for tropical cyclone warnings
. On October 12, as the storm was passing to the south of the island, officials closed all schools and government offices. Many private businesses closed as well.
At the time of Karen's landfall, gale warnings were issued for coastal waters, while inland wind warnings were in effect for Cape Breton
. In addition, heavy rainfall warnings were issued for large portions of Nova Scotia
including Halifax
, southeastern New Brunswick
, Fundy National Park
, and Prince Edward Island
.
between the precursor extratropical storm and high pressures resulted in strong winds on the island, including sustained winds of hurricane status at Fort George. Gusts on the island officially peaked at 100 mph (161 km/h) at Devonshire
. A cruise ship anchored at harbor reported a wind gust of 118 mph (190 km/h), though it could have been caused by a downdraft. The storm also dropped moderate rainfall of just over 3 inches (76 mm), resulting in minor flooding of streets. Because the storm developed quickly, wave-induced beach erosion was minor.
The strong winds left considerable tree and powerline damage. At the worst of the storm, 23,000 of the island's 30,000 power subscribers were without electricity
. Damage to power lines totaled to $385,000 (2001 USD, $468,700 2008 USD). The strong winds also caused considerable damage to vegetation. Three cruise ships weathered the storm at Saint George Harbour
, where the powerful winds ripped out a post and snapped a mooring line, leaving a ship drifting in the harbor. One crew member was minorly injured. Over a dozen boats broke free from their moorings, resulting in them running aground or sinking. In all, 87 boats were affected to some degree, with marine damage totaling to about $665,000 (2001 USD, $809,600 2008 USD). The winds also caused minor damage to 175 properties on the island, primarily to houses. Damage to houses amounted to about $425,000 (2001 USD, $517,400 2008 USD). Overall damage was moderate, totaling to about $1.4 million (2001 USD, $1.7 million 2008 USD). No fatalities were reported, though a few storm-related injuries occurred.
, peaking at 47 mph (76 km/h) with a gust of 64 mph (103 km/h) in Cape George
in Antigonish County, Nova Scotia
, along with a 26 mph (42 km/h) report in Charlottetown, Prince Edward Island. Rainband
s in the storm dropped light rainfall of up to 1.8 inches (46 mm) in Yarmouth, Nova Scotia
and 1.4 inches (35 mm) in Saint John, New Brunswick
, most of which fell in a short amount of time. Skewed to the left side of the transitioning storm, the rainfall was beneficial for the drought-stricken areas of Nova Scotia and New Brunswick. Due to the fast-moving nature of the storm, though, most areas reported only around half an inch of rain. A buoy in Halifax Harbour
reported wave heights of up to 16.7 feet (5.1 m), causing breaking waves at docks white caps along the ocean. Damage in Canada was minor due to the storm, limited to an uprooted tree in New Glasgow, Nova Scotia
and several other trees with damaged branches. There were no injuries or fatalities in Canada.
2001 Atlantic hurricane season
The 2001 Atlantic hurricane season was a fairly active Atlantic hurricane season that produced 17 tropical cyclones, 15 named storms, nine hurricanes, and four major hurricanes. The season officially lasted from June 1, 2001, to November 30, 2001, dates which by convention limit the period of each...
. It developed out of the interaction between a cold front and an upper level trough
Trough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts.Unlike fronts, there is not a universal symbol for a trough on a weather chart. The weather charts in some countries or regions mark troughs by a line. In the United States, a trough may be marked...
on October 10 located to the south of Bermuda
Bermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...
, and quickly strengthened as an extratropical storm. The storm passed near Bermuda on October 12, producing hurricane-force winds on the island. It then organized, becoming a subtropical cyclone
Subtropical cyclone
A subtropical cyclone is a weather system that has some characteristics of a tropical and an extratropical cyclone. As early as the 1950s, meteorologists were unclear whether they should be characterized as tropical or extratropical cyclones. They were officially recognized by the National...
on the 12th and a tropical cyclone
Tropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...
on the 13th. Karen strengthened to reach 80 mph (130 km/h) winds as a Category 1 hurricane on the Saffir-Simpson Hurricane Scale
Saffir-Simpson Hurricane Scale
The Saffir–Simpson Hurricane Scale , or the Saffir–Simpson Hurricane Wind Scale , classifies hurricanes — Western Hemisphere tropical cyclones that exceed the intensities of tropical depressions and tropical storms — into five categories distinguished by the intensities of their sustained winds...
, and after weakening over cooler waters, it made landfall on Nova Scotia
Nova Scotia
Nova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the...
as a tropical storm. It quickly became extratropical.
On Bermuda, winds from the precursor extratropical storm produced moderate damage, primarily to power lines and marine interests. Over 2/3 of the island's power subscribers were left without power during the worst of the storm, and several boats sank or ran aground from the high winds. Damage on Bermuda totaled to over $1.4 million (2001 USD; $1.7 million 2008 USD). In Atlantic Canada, Tropical Storm Karen produced light winds and rain, but caused minimal damage.
Meteorological history
A cold front stalled a couple hundred miles southeast of BermudaBermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...
on October 10. During that day, a strong upper-level trough
Trough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts.Unlike fronts, there is not a universal symbol for a trough on a weather chart. The weather charts in some countries or regions mark troughs by a line. In the United States, a trough may be marked...
moved southeastward off the southeast coast of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Due to several factors, including upward motion and strong diffluence—the rate at which a fluid moves—the area became baroclinically unstable. This caused the interaction between the trough and the front to develop into an extratropical low about 345 miles (555 km) southeast of Bermuda on October 11. The low moved quickly northward, then northwestward, strengthening quickly due to the instability of the atmosphere. Late on the 11th, the system slowed, and the upper-level circulation became aligned with the low-level circulation. The extratropical storm began to develop tropical characteristics
Tropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...
late on the 11th, including surface temperatures warmer than the surrounding environment, and vertical wind characteristics of a tropical cyclone. Based on its organization, the system developed into Subtropical Storm One early on October 12 while located about 35 miles (55 km) south of Bermuda.
While passing to the south of Bermuda, the subtropical storm
Subtropical cyclone
A subtropical cyclone is a weather system that has some characteristics of a tropical and an extratropical cyclone. As early as the 1950s, meteorologists were unclear whether they should be characterized as tropical or extratropical cyclones. They were officially recognized by the National...
maintained winds of 70 mph (110 km/h), with wind gusts on the island surpassing 100 mph (160 km/h). After becoming dissociated from the Westerlies
Westerlies
The Westerlies, anti-trades, or Prevailing Westerlies, are the prevailing winds in the middle latitudes between 30 and 60 degrees latitude, blowing from the high pressure area in the horse latitudes towards the poles. These prevailing winds blow from the west to the east, and steer extratropical...
, the system turned northward, and began to develop convection over the center. In addition, the frontal characteristics of the subtropical storm continually weakened. On October 13, based on an Advanced Microwave Sounding Unit
Advanced Microwave Sounding Unit
The Advanced microwave sounding unit is a multi-channel microwave radiometer installed on meteorological satellites. The instrument examines several bands of microwave radiation from the atmosphere to perform atmospheric sounding of temperature and moisture levels.-Products:Level-1 radiance data...
observation that stated that a warm core was present throughout the system, the National Hurricane Center
National Hurricane Center
The National Hurricane Center , located at Florida International University in Miami, Florida, is the division of the National Weather Service responsible for tracking and predicting weather systems within the tropics between the Prime Meridian and the 140th meridian west poleward to the 30th...
designated the system as a tropical storm, and gave it the name Karen
Karen (name)
In English, Karen is a mostly known as a feminine given name, derived from the Danish short form of Katherine.The name Karen was one of the top ten names for girls born in the United States during the 1950s and 1960s, peaking as the 3rd most popular girl's name in 1965.However, in Armenian, Karen...
. At this point, Karen was located 200 miles (320 km) north of Bermuda. Karen slowly strengthened over the warm waters of the Gulf Stream
Gulf Stream
The Gulf Stream, together with its northern extension towards Europe, the North Atlantic Drift, is a powerful, warm, and swift Atlantic ocean current that originates at the tip of Florida, and follows the eastern coastlines of the United States and Newfoundland before crossing the Atlantic Ocean...
, and the storm intensified to a hurricane later on October 13. Convection continued to develop, and organized into a ring around the eye
Eye (cyclone)
The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The eye of a storm is a roughly circular area and typically 30–65 km in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the second most severe weather of a cyclone...
as Karen reached its peak intensity of 80 mph (130 km/h) on October 14 while located about 400 miles (640 km) south of Halifax, Nova Scotia
City of Halifax
Halifax is a city in Canada, which was the capital of the province of Nova Scotia and shire town of Halifax County. It was the largest city in Atlantic Canada until it was amalgamated into Halifax Regional Municipality in 1996...
.
Karen quickly weakened as it moved over cooler waters, and late on October 14 it degenerated back into a tropical storm as it accelerated northward. Convection
Convection
Convection is the movement of molecules within fluids and rheids. It cannot take place in solids, since neither bulk current flows nor significant diffusion can take place in solids....
gradually decreased, and Karen made landfall on southwestern Nova Scotia
Nova Scotia
Nova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the...
with winds of 45 mph (70 km/h) on October 15. Karen retained its tropical characteristics during and after making landfall, based on a research flight out of Halifax intended to study the early stages of extratropical transition. The flight reported arced bands and a warm-core system transitioning into a more typical mid-latitude system. Under the influence of a mid-latitude system, the storm turned sharply to the northeast, and after losing the remaining of its convection it became extratropical shortly after landfall. Continuing northward, the remnant low quickly weakened, and dissipated as it was absorbed by a larger extratropical storm over the Gulf of Saint Lawrence
Gulf of Saint Lawrence
The Gulf of Saint Lawrence , the world's largest estuary, is the outlet of North America's Great Lakes via the Saint Lawrence River into the Atlantic Ocean...
.
Preparations
On October 10, as the precursor extratropical storm was forming, the Bermuda Weather ServiceBermuda Weather Service
The Bermuda Weather Service is Bermuda's national meteorological service. It provides public, marine, tropical and aviation weather forecasts as well as warnings and climatolological services. The service began operations under contract from the Department of Airport Operations, Ministry of...
issued a gale and later a storm warning for the island
Bermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...
, expecting winds of 50 to 60 mph (60 to 95 km/h). Several radio interviews and television stations issued information on the expected storm. Many residents believed they were insufficiently warned, though it is acknowledged that emergency managers and citizens pay less attention to gale warnings then they do for tropical cyclone warnings
Tropical cyclone warnings and watches
Warnings and watches are two levels of alert issued by national weather forecasting bodies to coastal areas threatened by the imminent approach of a tropical cyclone of tropical storm or hurricane intensity. They are notices to the local population and civil authorities to make appropriate...
. On October 12, as the storm was passing to the south of the island, officials closed all schools and government offices. Many private businesses closed as well.
At the time of Karen's landfall, gale warnings were issued for coastal waters, while inland wind warnings were in effect for Cape Breton
Cape Breton County, Nova Scotia
Cape Breton County, officially, County Cape Breton, is a county in the Canadian province of Nova Scotia, on Cape Breton Island.Taking its name from Cape Breton, the most easterly point of the island which was called after the Bretons of Brittany, this municipality has what is probably the oldest...
. In addition, heavy rainfall warnings were issued for large portions of Nova Scotia
Nova Scotia
Nova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the...
including Halifax
Halifax Regional Municipality, Nova Scotia
Halifax Regional Municipality is the capital of the province of Nova Scotia, Canada. The Regional Municipality had a 2006 census population of 372,679, while the metropolitan area had a 2010 estimated population of 403,188, and the urban area of Halifax had a population of 282,924...
, southeastern New Brunswick
New Brunswick
New Brunswick is one of Canada's three Maritime provinces and is the only province in the federation that is constitutionally bilingual . The provincial capital is Fredericton and Saint John is the most populous city. Greater Moncton is the largest Census Metropolitan Area...
, Fundy National Park
Fundy National Park
Fundy National Park is located on the Bay of Fundy, near the village of Alma, New Brunswick. The Park showcases both seashore habitats and highland Acadian forests...
, and Prince Edward Island
Prince Edward Island
Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population...
.
Bermuda
While passing to the south of the island, the tight pressure gradientPressure gradient
In atmospheric sciences , the pressure gradient is a physical quantity that describes in which direction and at what rate the pressure changes the most rapidly around a particular location. The pressure gradient is a dimensional quantity expressed in units of pressure per unit length...
between the precursor extratropical storm and high pressures resulted in strong winds on the island, including sustained winds of hurricane status at Fort George. Gusts on the island officially peaked at 100 mph (161 km/h) at Devonshire
Devonshire Parish, Bermuda
-Location:It is located in the centre of the territory, close to the junction between the main part of the main island and the peninsula containing the capital, Hamilton, and Pembroke Parish . To the northeast, it is joined to Smith's Parish, and to the southwest it borders Paget Parish. As with...
. A cruise ship anchored at harbor reported a wind gust of 118 mph (190 km/h), though it could have been caused by a downdraft. The storm also dropped moderate rainfall of just over 3 inches (76 mm), resulting in minor flooding of streets. Because the storm developed quickly, wave-induced beach erosion was minor.
The strong winds left considerable tree and powerline damage. At the worst of the storm, 23,000 of the island's 30,000 power subscribers were without electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
. Damage to power lines totaled to $385,000 (2001 USD, $468,700 2008 USD). The strong winds also caused considerable damage to vegetation. Three cruise ships weathered the storm at Saint George Harbour
St. George's, Bermuda
St. George's , located on the island and within the parish of the same names, was the first permanent settlement on the islands of Bermuda, and is often described as the third successful English settlement in the Americas, after St. John's, Newfoundland, and Jamestown, Virginia. However, St...
, where the powerful winds ripped out a post and snapped a mooring line, leaving a ship drifting in the harbor. One crew member was minorly injured. Over a dozen boats broke free from their moorings, resulting in them running aground or sinking. In all, 87 boats were affected to some degree, with marine damage totaling to about $665,000 (2001 USD, $809,600 2008 USD). The winds also caused minor damage to 175 properties on the island, primarily to houses. Damage to houses amounted to about $425,000 (2001 USD, $517,400 2008 USD). Overall damage was moderate, totaling to about $1.4 million (2001 USD, $1.7 million 2008 USD). No fatalities were reported, though a few storm-related injuries occurred.
Canada
Tropical Storm Karen produced light to moderate winds across Atlantic CanadaAtlantic Canada
Atlantic Canada is the region of Canada comprising the four provinces located on the Atlantic coast, excluding Quebec: the three Maritime provinces – New Brunswick, Prince Edward Island, and Nova Scotia – and Newfoundland and Labrador...
, peaking at 47 mph (76 km/h) with a gust of 64 mph (103 km/h) in Cape George
Cape George, Nova Scotia
Cape George is a headland and community of the same name located Antigonish County, Nova Scotia, Canada.It defines the northwestern limit of St. George's Bay....
in Antigonish County, Nova Scotia
Antigonish County, Nova Scotia
Antigonish County, Nova Scotia is a county in the Canadian province of Nova Scotia. It is located in northern Nova Scotia on the Northumberland Strait and its county seat is the town of Antigonish.-History:...
, along with a 26 mph (42 km/h) report in Charlottetown, Prince Edward Island. Rainband
Rainband
A rainband is a cloud and precipitation structure associated with an area of rainfall which is significantly elongated. Rainbands can be stratiform or convective, and are generated by differences in temperature. When noted on weather radar imagery, this precipitation elongation is referred to as...
s in the storm dropped light rainfall of up to 1.8 inches (46 mm) in Yarmouth, Nova Scotia
Yarmouth, Nova Scotia
Yarmouth is a town and fishing port located on the Gulf of Maine in rural southwestern Nova Scotia, Canada. It is the shire town of Yarmouth County. The town is located in the heart of the world's largest lobster fishing grounds and has Canada's highest lobster catch.- History :The townsite may...
and 1.4 inches (35 mm) in Saint John, New Brunswick
Saint John, New Brunswick
City of Saint John , or commonly Saint John, is the largest city in the province of New Brunswick, and the first incorporated city in Canada. The city is situated along the north shore of the Bay of Fundy at the mouth of the Saint John River. In 2006 the city proper had a population of 74,043...
, most of which fell in a short amount of time. Skewed to the left side of the transitioning storm, the rainfall was beneficial for the drought-stricken areas of Nova Scotia and New Brunswick. Due to the fast-moving nature of the storm, though, most areas reported only around half an inch of rain. A buoy in Halifax Harbour
Halifax Harbour
Halifax Harbour is a large natural harbour on the Atlantic coast of Nova Scotia, Canada, located in the Halifax Regional Municipality.-Harbour description:The harbour is called Jipugtug by the Mi'kmaq first nation, anglisized as Chebucto...
reported wave heights of up to 16.7 feet (5.1 m), causing breaking waves at docks white caps along the ocean. Damage in Canada was minor due to the storm, limited to an uprooted tree in New Glasgow, Nova Scotia
New Glasgow, Nova Scotia
New Glasgow is a town in Pictou County, in the province of Nova Scotia, Canada. It is situated on the banks of the East River of Pictou, which flows into Pictou Harbour, a sub-basin of the Northumberland Strait....
and several other trees with damaged branches. There were no injuries or fatalities in Canada.
See also
- Other storms of the same name
- Timeline of the 2001 Atlantic hurricane seasonTimeline of the 2001 Atlantic hurricane seasonThe timeline of the 2001 Atlantic hurricane season documents all the storm formations, strengthening, weakening, landfalls, extratropical transitions, as well as dissipation...