Braer Storm of January 1993
Encyclopedia
The Braer Storm of January 1993 is the most intense extratropical cyclone
on record for the northern Atlantic ocean
. Developing as a weak frontal wave on January 8, 1993, the system moved rapidly northeast developing at a moderate pace. The combination of the absorption of a second low-pressure area to its southeast, a stronger than normal sea surface temperature
differential along its path, and the presence of a strong jet stream
aloft led to a rapid strengthening of the storm, with its central pressure falling to an estimated 914 mb on January 10. Its strength was well predicted by forecasters in the United Kingdom
, and warnings were issued before the low initially developed.
Winds of gale
-force covered the far northern Atlantic between western Europe and Atlantic Canada
due to this storm, with hurricane-force winds confined near its center of circulation. After reaching its peak intensity, the system weakened as it moved into the far northeast Atlantic, dissipating by January 17. This storm caused blizzard
s across much of Scotland and led to the final breakup of the oil tanker MV Braer, which had been stranded in rocks off the Shetland Islands
by a previous storm nearly a week beforehand.
with very strong temperature
contrast, developed on the afternoon of January 8 to the southeast of Newfoundland
with a central pressure of 1008 mb. The system moved at a quick pace to the east-northeast at around 110 km/h (68.4 mph), deepening slowly. As the storm tracked more northeasterly, development accelerated, and early on the morning of January 9 its central pressure had fallen to 988 mb. A new low pressure area formed along the system's cold front to its south. By noon, the forward motion of the main cyclone accelerated to nearly 150 km/h (93.2 mph) and its central pressure began to bomb
, then down to 974 mb as it passed through the far northern Atlantic. This strengthening was enhanced by a strong jet stream with measured winds of 440 km/h (273.4 mph), and a stronger than normal sea surface temperature gradient along its path from the Grand Banks
towards Iceland.
The new low south of the main low strengthened quickly, and its central pressure dropped to 982 mb. During the evening of January 9, the main cyclone
to the north continued to bomb out, with a central pressure down to 958 mb. Soon afterwards, it absorbed the deepening low to its south and this merger caused a period of extreme intensification. By early morning of January 10, the pressure at the strong cyclone's center had fallen to 926 mb northwest of Great Britain
as it slowed its northeast motion. Hurricane-force winds of 122 km/h (75.8 mph) were recorded at a weather ship
just to its southeast. Towards sunrise, the center of the cyclone lay 300 km (186.4 mi) south-southeast of Iceland. The system continued to slow as it turned north-northeast, reaching its estimated lowest pressure of 914 mb later that morning. Weather buoys in the region with identifiers of 44746 and 64043 were not designed to read pressures below 925 mb, so when their pressures dropped to that reading, they stayed there until the storm moved away.
Its strongest winds were within 280 km (174 mi) of its center, and the pressure difference within that region implied sustained wind speeds of 190 km/h (118.1 mph) were possible. Early on the afternoon of January 10, a tremendous pressure differential existed between the center of the cyclone and a high-pressure area over Spain
, which had a central pressure of 1035 mb. This caused an extensive area of gale
-force winds which stretched from Newfoundland to Spain, and northeastward between Greenland and northern Norway
. A large area of hurricane-force winds existed within this area of gales. The center of the low transcribed a loop before resuming a slow northeast motion into the far northeast Atlantic. However, the system began to weaken, and by evening on January 10 its central pressure had risen to 920 mb. By the evening of January 12, its central pressure rose to 952 mb. During the evening of January 13, its central pressure rose to 961 mb while located in the far northeast Atlantic. Within four days, the low dissipated west of Norway.
global weather forecast
model as far as 84 hours in advance, which allowed forecasters in the United Kingdom to issue warnings related to the storm on the morning of January 8, before the cyclone had initially developed. The sign of the North Atlantic oscillation
switched from positive to weakly negative during the lifetime of this storm, which caused colder conditions to prevail in the eastern United States
and western Europe by the time the system was dissipating. The British Isles saw their pressures fall as low as 957 mb during the mid-afternoon of January 11 in extreme northwest Scotland
in Shetland-Lerwick. Winds gusted to 194 km/h (120.5 mph) at two locations: the weather ship Cumulus and North Rona
, north of Scotland. Wind gusts of over 190 km/h (118.1 mph) were measured across northwest Scotland. The highest precipitation amount
recorded with this system across Great Britain was 37.2 millimetres (1.5 in) at Cilfynydd
in South Wales
.
Periods of rain impacted the British Isles early in the morning of January 10, progressing from west to east. Wet and windy weather was seen across the region during the day, with a wintry mix of precipitation falling across northern sections of England and Scotland. Within the area of wintry mix, the wind combined with the ongoing snowfall led to blizzards across most of Scotland. Precipitation became more showery in nature during the evening hours. Thunderstorms were observed despite the near-freezing temperature readings. Wind and waves associated with this storm were too much for the tanker MV Braer, which had become lodged on rocks in the Shetland Islands nearly a week beforehand. The tanker broke up and its remaining cargo of 84,500 tons of light crude oil
spilled into the ocean surrounding those islands. The rough conditions caused by this storm led to the rapid breakup of visible oil slicks.
Extratropical cyclone
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are a group of cyclones defined as synoptic scale low pressure weather systems that occur in the middle latitudes of the Earth having neither tropical nor polar characteristics, and are connected with fronts and...
on record for the northern Atlantic ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
. Developing as a weak frontal wave on January 8, 1993, the system moved rapidly northeast developing at a moderate pace. The combination of the absorption of a second low-pressure area to its southeast, a stronger than normal sea surface temperature
Sea surface temperature
Sea surface temperature is the water temperature close to the oceans surface. The exact meaning of surface varies according to the measurement method used, but it is between and below the sea surface. Air masses in the Earth's atmosphere are highly modified by sea surface temperatures within a...
differential along its path, and the presence of a strong jet stream
Jet stream
Jet streams are fast flowing, narrow air currents found in the atmospheres of some planets, including Earth. The main jet streams are located near the tropopause, the transition between the troposphere and the stratosphere . The major jet streams on Earth are westerly winds...
aloft led to a rapid strengthening of the storm, with its central pressure falling to an estimated 914 mb on January 10. Its strength was well predicted by forecasters in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, and warnings were issued before the low initially developed.
Winds of gale
Gale
A gale is a very strong wind. There are conflicting definitions of how strong a wind must be to be considered a gale. The U.S. government's National Weather Service defines a gale as 34–47 knots of sustained surface winds. Forecasters typically issue gale warnings when winds of this strength are...
-force covered the far northern Atlantic between western Europe and Atlantic Canada
Atlantic 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...
due to this storm, with hurricane-force winds confined near its center of circulation. After reaching its peak intensity, the system weakened as it moved into the far northeast Atlantic, dissipating by January 17. This storm caused blizzard
Blizzard
A blizzard is a severe snowstorm characterized by strong winds. By definition, the difference between blizzard and a snowstorm is the strength of the wind. To be a blizzard, a snow storm must have winds in excess of with blowing or drifting snow which reduces visibility to 400 meters or ¼ mile or...
s across much of Scotland and led to the final breakup of the oil tanker MV Braer, which had been stranded in rocks off the Shetland Islands
Shetland Islands
Shetland is a subarctic archipelago of Scotland that lies north and east of mainland Great Britain. The islands lie some to the northeast of Orkney and southeast of the Faroe Islands and form part of the division between the Atlantic Ocean to the west and the North Sea to the east. The total...
by a previous storm nearly a week beforehand.
Meteorological history
A weak frontal wave, a low-pressure system forming along a weather frontWeather front
A weather front is a boundary separating two masses of air of different densities, and is the principal cause of meteorological phenomena. In surface weather analyses, fronts are depicted using various colored lines and symbols, depending on the type of front...
with very strong temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
contrast, developed on the afternoon of January 8 to the southeast of Newfoundland
Newfoundland and Labrador
Newfoundland and Labrador is the easternmost province of Canada. Situated in the country's Atlantic region, it incorporates the island of Newfoundland and mainland Labrador with a combined area of . As of April 2011, the province's estimated population is 508,400...
with a central pressure of 1008 mb. The system moved at a quick pace to the east-northeast at around 110 km/h (68.4 mph), deepening slowly. As the storm tracked more northeasterly, development accelerated, and early on the morning of January 9 its central pressure had fallen to 988 mb. A new low pressure area formed along the system's cold front to its south. By noon, the forward motion of the main cyclone accelerated to nearly 150 km/h (93.2 mph) and its central pressure began to bomb
Bomb (meteorology)
Bomb is a meteorological term for a baroclinic low pressure area characterized by a rapid pressure fall of at least 24 millibars in 24 hours. It is applied only to cold-air storms...
, then down to 974 mb as it passed through the far northern Atlantic. This strengthening was enhanced by a strong jet stream with measured winds of 440 km/h (273.4 mph), and a stronger than normal sea surface temperature gradient along its path from the Grand Banks
Grand Banks
The Grand Banks of Newfoundland are a group of underwater plateaus southeast of Newfoundland on the North American continental shelf. These areas are relatively shallow, ranging from in depth. The cold Labrador Current mixes with the warm waters of the Gulf Stream here.The mixing of these waters...
towards Iceland.
The new low south of the main low strengthened quickly, and its central pressure dropped to 982 mb. During the evening of January 9, the main cyclone
Cyclone
In meteorology, a cyclone is an area of closed, circular fluid motion rotating in the same direction as the Earth. This is usually characterized by inward spiraling winds that rotate anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere of the Earth. Most large-scale...
to the north continued to bomb out, with a central pressure down to 958 mb. Soon afterwards, it absorbed the deepening low to its south and this merger caused a period of extreme intensification. By early morning of January 10, the pressure at the strong cyclone's center had fallen to 926 mb northwest of Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
as it slowed its northeast motion. Hurricane-force winds of 122 km/h (75.8 mph) were recorded at a weather ship
Weather ship
A weather ship was a ship stationed in the ocean as a platform for surface and upper air meteorological observations for use in weather forecasting. They were primarily located in the north Atlantic and north Pacific oceans, reporting via radio...
just to its southeast. Towards sunrise, the center of the cyclone lay 300 km (186.4 mi) south-southeast of Iceland. The system continued to slow as it turned north-northeast, reaching its estimated lowest pressure of 914 mb later that morning. Weather buoys in the region with identifiers of 44746 and 64043 were not designed to read pressures below 925 mb, so when their pressures dropped to that reading, they stayed there until the storm moved away.
Its strongest winds were within 280 km (174 mi) of its center, and the pressure difference within that region implied sustained wind speeds of 190 km/h (118.1 mph) were possible. Early on the afternoon of January 10, a tremendous pressure differential existed between the center of the cyclone and a high-pressure area over Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
, which had a central pressure of 1035 mb. This caused an extensive area of gale
Gale
A gale is a very strong wind. There are conflicting definitions of how strong a wind must be to be considered a gale. The U.S. government's National Weather Service defines a gale as 34–47 knots of sustained surface winds. Forecasters typically issue gale warnings when winds of this strength are...
-force winds which stretched from Newfoundland to Spain, and northeastward between Greenland and northern Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
. A large area of hurricane-force winds existed within this area of gales. The center of the low transcribed a loop before resuming a slow northeast motion into the far northeast Atlantic. However, the system began to weaken, and by evening on January 10 its central pressure had risen to 920 mb. By the evening of January 12, its central pressure rose to 952 mb. During the evening of January 13, its central pressure rose to 961 mb while located in the far northeast Atlantic. Within four days, the low dissipated west of Norway.
Preparations and impact
The strength of this storm was well forecast by the British Met OfficeMet Office
The Met Office , is the United Kingdom's national weather service, and a trading fund of the Department for Business, Innovation and Skills...
global weather forecast
Weather forecasting
Weather forecasting is the application of science and technology to predict the state of the atmosphere for a given location. Human beings have attempted to predict the weather informally for millennia, and formally since the nineteenth century...
model as far as 84 hours in advance, which allowed forecasters in the United Kingdom to issue warnings related to the storm on the morning of January 8, before the cyclone had initially developed. The sign of the North Atlantic oscillation
North Atlantic oscillation
The North Atlantic oscillation is a climatic phenomenon in the North Atlantic Ocean of fluctuations in the difference of atmospheric pressure at sea level between the Icelandic low and the Azores high. Through east-west oscillation motions of the Icelandic low and the Azores high, it controls the...
switched from positive to weakly negative during the lifetime of this storm, which caused colder conditions to prevail in the eastern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and western Europe by the time the system was dissipating. The British Isles saw their pressures fall as low as 957 mb during the mid-afternoon of January 11 in extreme northwest Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
in Shetland-Lerwick. Winds gusted to 194 km/h (120.5 mph) at two locations: the weather ship Cumulus and North Rona
North Rona
Rona is a remote Scottish island in the North Atlantic. Rona is often referred to as North Rona in order to distinguish it from South Rona . It has an area of and a maximum height of...
, north of Scotland. Wind gusts of over 190 km/h (118.1 mph) were measured across northwest Scotland. The highest precipitation amount
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...
recorded with this system across Great Britain was 37.2 millimetres (1.5 in) at Cilfynydd
Cilfynydd
Cilfynydd is a village in South Wales a mile from the South Wales Valleys town of Pontypridd, and 13 miles north of the capital city Cardiff.- History :...
in South Wales
South Wales
South Wales is an area of Wales bordered by England and the Bristol Channel to the east and south, and Mid Wales and West Wales to the north and west. The most densely populated region in the south-west of the United Kingdom, it is home to around 2.1 million people and includes the capital city of...
.
Periods of rain impacted the British Isles early in the morning of January 10, progressing from west to east. Wet and windy weather was seen across the region during the day, with a wintry mix of precipitation falling across northern sections of England and Scotland. Within the area of wintry mix, the wind combined with the ongoing snowfall led to blizzards across most of Scotland. Precipitation became more showery in nature during the evening hours. Thunderstorms were observed despite the near-freezing temperature readings. Wind and waves associated with this storm were too much for the tanker MV Braer, which had become lodged on rocks in the Shetland Islands nearly a week beforehand. The tanker broke up and its remaining cargo of 84,500 tons of light crude oil
Light crude oil
Light crude oil is liquid petroleum that has a low density and flows freely at room temperature. It has a low viscosity, low specific gravity and high API gravity due to the presence of a high proportion of light hydrocarbon fractions. It generally has a low wax content...
spilled into the ocean surrounding those islands. The rough conditions caused by this storm led to the rapid breakup of visible oil slicks.