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Hurricane Irene (2005)
Encyclopedia
Hurricane Irene was a long-lived Cape Verde-type
Atlantic hurricane during the 2005 Atlantic hurricane season
. The storm formed near Cape Verde
on August 4 and crossed the Atlantic, turning northward around Bermuda
before becoming extratropical
southeast of Newfoundland. Irene persisted for 14 days as a tropical system, the longest duration of any storm of the 2005 season. It was the ninth named storm and fourth hurricane of the record-breaking season.
Irene proved to be a difficult storm to forecast due to oscillations in strength. After almost dissipating on August 10, Irene peaked as a Category 2 hurricane
on August 16 before being absorbed by a larger extratropical system late on August 18. Although there were initial fears of a landfall
in the United States due to uncertainty in predicting the storm's track, Hurricane Irene never approached land and caused no recorded damage. However, swells
up to 8 ft (2.4 m) and strong rip currents resulted in one fatality in Long Beach, New York
.
moved off the west coast of Africa on August 1, initially weakening due to cooler sea surface temperatures. It moved westward and passed near Cape Verde
, where convection
started to increase. The system became more organized and developed into Tropical Depression Nine on the afternoon of August 4, 690 miles (1100 km) southwest of the Cape Verde Islands. Early on August 5, the depression abruptly turned to the northwest into an area of higher wind shear
, causing some computer models to predict that the depression would dissipate, while others predicted steady strengthening. The sudden threat to the storm's existence prompted National Hurricane Center
(NHC) forecaster Dr Lixion Avila
to comment, "How little we know about the genesis of tropical cyclones." Despite the unfavorable conditions in its vicinity and its poor organization, Tropical Depression Nine continued to strengthen, becoming Tropical Storm Irene on August 7.
Because Irene was in an environment laden with dry air and high shear, it soon weakened to a tropical depression, on August 8. On the morning of August 10, as it was passing north of the Lesser Antilles
, Irene nearly dissipated into a remnant low, but forecasters predicted with "very low confidence" that the storm would survive. However, warmer waters and less wind shear allowed Irene to become gradually more organized while south of Bermuda
, and it became a tropical storm once again early on August 11.
Due to uncertainties about how the region's subtropical ridge
would interact with Irene, the models continued to give unclear signals of the storm's future. Some of the models predicted that Irene would make landfall
in North Carolina
, while others continued to anticipate that Irene would dissipate. The uncertainty ended when a weakness in the subtropical ridge allowed Irene to turn sharply northward, which caused the storm to pass midway between the Outer Banks
of North Carolina and Bermuda on August 15. Soon after, upper-level shear weakened greatly, and Irene rapidly intensified, first to a hurricane, then to its peak strength as a 105 mph (170 km/h) Category 2 hurricane
on the afternoon of August 16, while located 350 miles (560 km) northeast of Bermuda; at the same time it also attained minimum pressure of 970 mbar
. Though NHC meteorologists thought it was likely that Irene would become a hurricane, they were not expecting an intensification of such a magnitude.
Irene entered a region of increased wind shear and began to weaken, and as a result it was downgraded to a tropical storm early on August 18, when it was 520 miles (830 km) south of Cape Race
, Newfoundland. Tropical Storm Irene finally became extratropical
on August 18 after moving over much cooler waters, and was absorbed by a larger extratropical system later that day. Irene lasted for 14 days as a tropical system, the longest duration of any storm of the 2005 season.
were issued for it. Despite Irene's long life there were no reports of tropical storm force winds affecting ships. There were no damage or fatalities as a result of Irene. However, the hurricane generated strong waves and increased the risk of rip current
s along the East Coast of the United States
. Many beaches in New Jersey
restricted swimming activities, and lifeguard
s at one beach performed more than a hundred rescues over a three-day period. Waves along the coastline of New York reached 4 to 8 ft (1.2 to 2.4 m). On August 14, a 16-year-old boy drowned after being caught in a rip current near Long Beach, New York
on August 14. His body was recovered on August 16 after washing ashore.
When Tropical Storm Irene formed on August 7, it was the earliest date for the formation of the ninth tropical storm in an Atlantic hurricane season, beating the previous record held by a storm in the 1936 season
by 13 days. This storm also marked the fifth occasion the name "Irene" had been used to name a tropical cyclone in the Atlantic. Due to the lack of effects on land from Hurricane Irene, the name was not retired by the World Meteorological Organization
and was reused
in the 2011 Atlantic season
.
Cape Verde-type hurricane
A Cape Verde-type hurricane is an Atlantic hurricane that develops near the Cape Verde islands, off the west coast of Africa. The average hurricane season has about two Cape Verde-type hurricanes, which are usually the largest and most intense storms of the season because they often have plenty of...
Atlantic hurricane during the 2005 Atlantic hurricane season
2005 Atlantic hurricane season
The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in recorded history, repeatedly shattering numerous records. The impact of the season was widespread and ruinous with an estimated 3,913 deaths and record damage of about $159.2 billion...
. The storm formed near Cape Verde
Cape Verde
The Republic of Cape Verde is an island country, spanning an archipelago of 10 islands located in the central Atlantic Ocean, 570 kilometres off the coast of Western Africa...
on August 4 and crossed the Atlantic, turning northward around 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...
before becoming extratropical
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...
southeast of Newfoundland. Irene persisted for 14 days as a tropical system, the longest duration of any storm of the 2005 season. It was the ninth named storm and fourth hurricane of the record-breaking season.
Irene proved to be a difficult storm to forecast due to oscillations in strength. After almost dissipating on August 10, Irene peaked as a Category 2 hurricane
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...
on August 16 before being absorbed by a larger extratropical system late on August 18. Although there were initial fears of a landfall
Landfall (meteorology)
Landfall is the event of a tropical cyclone or a waterspout coming onto land after being over water. When a waterspout makes landfall it is reclassified as a tornado, which can then cause damage inland...
in the United States due to uncertainty in predicting the storm's track, Hurricane Irene never approached land and caused no recorded damage. However, swells
Swell (ocean)
A swell, in the context of an ocean, sea or lake, is a series surface gravity waves that is not generated by the local wind. Swell waves often have a long wavelength but this varies with the size of the water body, e.g. rarely more than 150 m in the Mediterranean, and from event to event, with...
up to 8 ft (2.4 m) and strong rip currents resulted in one fatality in Long Beach, New York
Long Beach, New York
Long Beach is a city in Nassau County, New York. Just south of Long Island, it is located on Long Beach Barrier Island, which is the westernmost of the outer barrier islands off Long Island's South Shore. As of the United States 2010 Census, the city population was 33,275...
.
Meteorological history
A vigorous tropical waveTropical wave
Tropical waves, easterly waves, or tropical easterly waves, also known as African easterly waves in the Atlantic region, are a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which move from east to west across the tropics causing areas of...
moved off the west coast of Africa on August 1, initially weakening due to cooler sea surface temperatures. It moved westward and passed near Cape Verde
Cape Verde
The Republic of Cape Verde is an island country, spanning an archipelago of 10 islands located in the central Atlantic Ocean, 570 kilometres off the coast of Western Africa...
, where convection
Atmospheric convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference, layer in the atmosphere. Different lapse rates within dry and moist air lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to...
started to increase. The system became more organized and developed into Tropical Depression Nine on the afternoon of August 4, 690 miles (1100 km) southwest of the Cape Verde Islands. Early on August 5, the depression abruptly turned to the northwest into an area of higher wind shear
Wind shear
Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere...
, causing some computer models to predict that the depression would dissipate, while others predicted steady strengthening. The sudden threat to the storm's existence prompted 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...
(NHC) forecaster Dr Lixion Avila
Lixion Avila
Dr. Lixion Avila is a weather forecaster with the National Hurricane Center . He has been a senior hurricane specialist there since 1987 and is the longest-tenured senior specialist....
to comment, "How little we know about the genesis of tropical cyclones." Despite the unfavorable conditions in its vicinity and its poor organization, Tropical Depression Nine continued to strengthen, becoming Tropical Storm Irene on August 7.
Because Irene was in an environment laden with dry air and high shear, it soon weakened to a tropical depression, on August 8. On the morning of August 10, as it was passing north of the Lesser Antilles
Lesser Antilles
The Lesser Antilles are a long, partly volcanic island arc in the Western Hemisphere. Most of its islands form the eastern boundary of the Caribbean Sea with the Atlantic Ocean, with the remainder located in the southern Caribbean just north of South America...
, Irene nearly dissipated into a remnant low, but forecasters predicted with "very low confidence" that the storm would survive. However, warmer waters and less wind shear allowed Irene to become gradually more organized while 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 it became a tropical storm once again early on August 11.
Due to uncertainties about how the region's subtropical ridge
Subtropical ridge
The subtropical ridge is a significant belt of high pressure situated around the latitudes of 30°N in the Northern Hemisphere and 30°S in the Southern Hemisphere. It is characterized by mostly calm winds, which acts to reduce air quality under its axis by causing fog overnight, and haze during...
would interact with Irene, the models continued to give unclear signals of the storm's future. Some of the models predicted that Irene would make landfall
Landfall (meteorology)
Landfall is the event of a tropical cyclone or a waterspout coming onto land after being over water. When a waterspout makes landfall it is reclassified as a tornado, which can then cause damage inland...
in North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, while others continued to anticipate that Irene would dissipate. The uncertainty ended when a weakness in the subtropical ridge allowed Irene to turn sharply northward, which caused the storm to pass midway between the Outer Banks
Outer Banks
The Outer Banks is a 200-mile long string of narrow barrier islands off the coast of North Carolina, beginning in the southeastern corner of Virginia Beach on the east coast of the United States....
of North Carolina and Bermuda on August 15. Soon after, upper-level shear weakened greatly, and Irene rapidly intensified, first to a hurricane, then to its peak strength as a 105 mph (170 km/h) Category 2 hurricane
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...
on the afternoon of August 16, while located 350 miles (560 km) northeast of Bermuda; at the same time it also attained minimum pressure of 970 mbar
Bar (unit)
The bar is a unit of pressure equal to 100 kilopascals, and roughly equal to the atmospheric pressure on Earth at sea level. Other units derived from the bar are the megabar , kilobar , decibar , centibar , and millibar...
. Though NHC meteorologists thought it was likely that Irene would become a hurricane, they were not expecting an intensification of such a magnitude.
Irene entered a region of increased wind shear and began to weaken, and as a result it was downgraded to a tropical storm early on August 18, when it was 520 miles (830 km) south of Cape Race
Cape Race
Cape Race is a point of land located at the southeastern tip of the Avalon Peninsula on the island of Newfoundland, Canada. Its name is thought to come from the original Portuguese name for this cape, "Raso", or "bare"...
, Newfoundland. Tropical Storm Irene finally became extratropical
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 August 18 after moving over much cooler waters, and was absorbed by a larger extratropical system later that day. Irene lasted for 14 days as a tropical system, the longest duration of any storm of the 2005 season.
Impact, records and naming
As Hurricane Irene stayed well away from land, no coastal warnings or watchesTropical 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...
were issued for it. Despite Irene's long life there were no reports of tropical storm force winds affecting ships. There were no damage or fatalities as a result of Irene. However, the hurricane generated strong waves and increased the risk of rip current
Rip current
A rip current, commonly referred to by the misnomer rip tide, is a strong channel of water flowing seaward from near the shore, typically through the surf line. Typical flow is at 0.5 metres per second , and can be as fast as 2.5 metres per second...
s along the East Coast of the United States
East Coast of the United States
The East Coast of the United States, also known as the Eastern Seaboard, refers to the easternmost coastal states in the United States, which touch the Atlantic Ocean and stretch up to Canada. The term includes the U.S...
. Many beaches in New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
restricted swimming activities, and lifeguard
Lifeguard
A lifeguard supervises the safety and rescue of swimmers, surfers, and other water sports participants such as in a swimming pool, water park, or beach. Lifeguards are strong swimmers and trained in first aid, certified in water rescue using a variety of aids and equipment depending on...
s at one beach performed more than a hundred rescues over a three-day period. Waves along the coastline of New York reached 4 to 8 ft (1.2 to 2.4 m). On August 14, a 16-year-old boy drowned after being caught in a rip current near Long Beach, New York
Long Beach, New York
Long Beach is a city in Nassau County, New York. Just south of Long Island, it is located on Long Beach Barrier Island, which is the westernmost of the outer barrier islands off Long Island's South Shore. As of the United States 2010 Census, the city population was 33,275...
on August 14. His body was recovered on August 16 after washing ashore.
When Tropical Storm Irene formed on August 7, it was the earliest date for the formation of the ninth tropical storm in an Atlantic hurricane season, beating the previous record held by a storm in the 1936 season
1936 Atlantic hurricane season
The 1936 Atlantic hurricane season officially began on June 16, 1936, and lasted until October 31, 1936. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin....
by 13 days. This storm also marked the fifth occasion the name "Irene" had been used to name a tropical cyclone in the Atlantic. Due to the lack of effects on land from Hurricane Irene, the name was not retired by the World Meteorological Organization
World Meteorological Organization
The World Meteorological Organization is an intergovernmental organization with a membership of 189 Member States and Territories. It originated from the International Meteorological Organization , which was founded in 1873...
and was reused
Hurricane Irene (2011)
Hurricane Irene was a large and powerful Atlantic hurricane that left extensive flood and wind damage along its path through the Caribbean, the United States East Coast and as far north as Atlantic Canada in 2011...
in the 2011 Atlantic season
2011 Atlantic hurricane season
The 2011 Atlantic hurricane season is tied for the third most active season on record with 1887, 1995 and 2010. It began on June 1, 2011, and ended on November 30, 2011, however these dates conventionally delimit the period of each year when most tropical cyclones develop in the Atlantic basin...
.
See also
- List of 2005 Atlantic hurricane season storms
- Timeline of the 2005 Atlantic hurricane seasonTimeline of the 2005 Atlantic hurricane seasonThe timeline of the 2005 Atlantic hurricane season documents the formations, strengthenings, weakenings, landfalls, extratropical transitions, and dissipations of the season's tropical and subtropical storms. The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in...
- List of New Jersey hurricanes