Tropical Storm Erika (2009)
Encyclopedia
Tropical Storm Erika was a short-lived tropical cyclone
that had minor impacts in the Lesser Antilles
. The fifth named storm of the 2009 Atlantic hurricane season
, Erika originated out of a tropical wave
on September 1 near the Lesser Antilles
. Although it was a disorganized system, it was immediately declared a tropical storm, rather than a tropical depression. Later that day, the system reached its peak intensity with winds of 50 mph (85 km/h) and a barometric pressure of 1004 mbar (hPa; 29.65 inHg). Increased wind shear
caused the storm to weaken shortly thereafter, with Erika barely maintaining tropical storm-status by September 2. Later that day, the storm passed over the island of Guadeloupe
and entered the Caribbean Sea
. On September 3, Erika weakened to a tropical depression as the low pressure center became fully displaced from convective activity
. Later that day, the system degenerated into a remnant low before dissipating near Puerto Rico on September 4.
Due to the storm's low intensity, Erika produced little damage in the Lesser Antilles
during its passage through the islands. Guadeloupe recorded up to 12.1 in (307.3 mm) of rain, leading to flooding and some landslides; 12,000 people on the island were left without power. Several other islands recorded moderate rainfall form the system before the tropical storm degenerated into a remnant low. In Puerto Rico, the cyclone's remnants produced heavy rainfall, peaking at 7.58 in (192.5 mm), that triggered flooding in several regions.
accompanied by disorganized shower and thunderstorm activity
that moved off the west coast of Africa, near the Cape Verde Islands, on August 25. The following day, convection
surrounding the wave began to show signs of organization as it tracked westward across the Atlantic. By August 28, an area of low pressure
developed from the wave. Environmental conditions ahead of the low were favorable for further development of the system. Despite the favorable conditions, the low became increasingly disorganized on August 29, with little convection remaining around the center of circulation. The next day, the system quickly became organized, with shower and thunderstorms developing around the center and the National Hurricane Center
(NHC) noted that the low would likely become a tropical depression within 24 hours. Although convection was well-organized, the system lacked a defined low-level circulation center, leading to the NHC not issuing advisories on the system at that time.
On September 1, a Hurricane Hunter reconnaissance mission into the low found a closed circulation center and tropical storm-force winds. Upon fiding the low-level circulation center, the NHC began monitoring the system as Tropical Storm Erika, the fifth named storm of the 2009 season. Erika was slightly disorganized due to moderate wind shear
, with the center partially devoid of convection. However, with warm sea surface temperature
s, the storm was forecast to intensify to a strong tropical storm within a few days. A mid-level ridge
to the north led to Erika maintaining a general westward track for most of its existence. Several hours after being classified, the storm reached its peak intensity with winds of 50 mph (85 km/h) and a barometric pressure of 1004 mbar (hPa; 29.65 inHg). However, the peak intensity was operationally placed at 60 mph (95 km/h) based on readings from reconnaissance missions. In post-storm analysis of these readings, it was determined that the NHC had over estimated the wind speeds in an area of unusually heavy rains. By the morning of September 2, Erika became significantly disorganized, and Hurricane Hunters reported the possibility that multiple circulation centers existed within the broader storm system.
Wind shear began to increase earlier than forecast models anticipated, causing the storm to weaken into a minimal tropical storm later that morning. Around 1830 UTC
, the center of Erika passed over the island of Guadeloupe
with winds of 40 mph (65 km/h) as the storm entered the eastern Caribbean Sea
. The circulation later became elongated and began to degenerate into a trough of low pressure
. The NHC noted that due to the large size of the overall system, the center of Erika could reform elsewhere and restrengthen. Following a brief increase in convective activity, the storm slightly intensified before succumbing to wind shear once more. By the afternoon of September 3, the center of Erika was fully devoid of convection and the NHC downgraded it to a tropical depression. Shortly after, the system degenerated into a remnant low, coinciding with the issuance of the final advisory from the NHC. The following day, the remnants approached the southern coast of Puerto Rico, producing heavy rainfall across the island. The system was last noted later on September 4 as it dissipated roughly 80 mi (140 km) south of Puerto Rico.
were issued for St. Maarten, Antigua
, Barbuda
, St. Kitts, Nevis
, Anguilla
, St. Martin and Saint Barthélemy
. The following day, all of the watches were upgraded to tropical storm warnings as Erika neared the Lesser Antilles
. When the storm entered the Caribbean Sea, a tropical storm warning was issued for Dominica
and tropical storm watches were for Puerto Rico
, the U.S. Virgin Islands and the British Virgin Islands
. Early on September 3, the tropical storm watches were upgraded to warnings as Erika drifted through the eastern Caribbean. Later that day, the warnings for Dominica and Guadeloupe were discontinued. Shortly thereafter, all remaining warnings were canceled.
Exports from the Hovensa oil refinery in St. Croix, with a daily production of roughly 500000 barrels (79,493.6 m³), were canceled as ports across the island were closed. All businesses were shut down in Dominica on September 3 due to the storm. In Antigua and Barbuda, all schools and the local airport were closed as a precautionary measure. Two cruise ships, the Carnival Glory
and a Royal Caribbean
ship postponed their docking dates and stayed at sea for a few additional days. The islands of Saint Martin and Saint Barthélemy were placed under an orange alert, the second-lowest alert level, and Guadeloupe was placed under a yellow alert, the lowest alert level. In Puerto Rico, officials closed schools and government offices on September 4 and opened 433 shelters across the island. Officials in the Dominican Republic placed nine provinces under warnings as a precautionary measure. Nearby Haiti
was also alerted of the possibility of heavy rains.
at 12.1 in (307.3 mm), of which a record 9.4 in (238.8 mm) fell in 24 hours. Sustained winds reached 56 mph (90 km/h) on the island of Marie Galante. One rock slide occurred near Losteau, in Bouillante. Several roads became impassable due to flood waters. At the height of the storm, an estimated 12,000 people were without power across the island. Up to 5.5 in (139.7 mm) of rain fell along the foothills in Trinidad
. In St. Martin, a peak of 3.7 in (94 mm) of rain fell. In the United States Virgin Islands
, up to 1.61 in (40.9 mm) of rain fell in a 24 hour span, resulting in minor flooding.
In Puerto Rico, the remnants of Erika produced significant amounts of rainfall, causing the rivers of La Plata, Loíza, and Caguitas to overflow their banks and trigger widespread flooding. A weather station in Naguabo recorded 7.92 in (201.2 mm) of precipitation. Several other areas recorded upwards of 4 in (101.6 mm). In the municipality of Guanica, several homes were flooded, leaving $5,000 in damage. The most severe damage took place in the municipality of Las Piedras where $15,000 was reported in flood losses. One river rose to a level of 29.27 ft (8.9 m), 7.27 ft (2.2 m) above flood stage. Damage in Fajardo was estimated at $10,000 after homes were inundated by flood waters. Additionally, flooding in Caguas resulted in $5,000 in damage. In the Dominican Republic flood warnings were issued for the provinces of La Altagracia, El Seibo, Hato Mayor, Monte Plata, Samana, Duarte and Maria Trinidad Sanchez due the threat of continued rainfall and flooding.
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...
that had minor impacts in 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...
. The fifth named storm of the 2009 Atlantic hurricane season
2009 Atlantic hurricane season
The 2009 Atlantic hurricane season was a below-average year, unlike the 2009 Pacific hurricane season, which was above average, both due to a moderate El Niño. During this year, nine tropical storms formed, the fewest since the 1997 season.An average season has ten tropical storms, six hurricanes...
, Erika originated out of a tropical wave
Tropical 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...
on September 1 near 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...
. Although it was a disorganized system, it was immediately declared a tropical storm, rather than a tropical depression. Later that day, the system reached its peak intensity with winds of 50 mph (85 km/h) and a barometric pressure of 1004 mbar (hPa; 29.65 inHg). Increased 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...
caused the storm to weaken shortly thereafter, with Erika barely maintaining tropical storm-status by September 2. Later that day, the storm passed over the island of Guadeloupe
Guadeloupe
Guadeloupe is an archipelago located in the Leeward Islands, in the Lesser Antilles, with a land area of 1,628 square kilometres and a population of 400,000. It is the first overseas region of France, consisting of a single overseas department. As with the other overseas departments, Guadeloupe...
and entered the Caribbean Sea
Caribbean Sea
The Caribbean Sea is a sea of the Atlantic Ocean located in the tropics of the Western hemisphere. It is bounded by Mexico and Central America to the west and southwest, to the north by the Greater Antilles, and to the east by the Lesser Antilles....
. On September 3, Erika weakened to a tropical depression as the low pressure center became fully displaced from convective activity
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...
. Later that day, the system degenerated into a remnant low before dissipating near Puerto Rico on September 4.
Due to the storm's low intensity, Erika produced little damage in 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...
during its passage through the islands. Guadeloupe recorded up to 12.1 in (307.3 mm) of rain, leading to flooding and some landslides; 12,000 people on the island were left without power. Several other islands recorded moderate rainfall form the system before the tropical storm degenerated into a remnant low. In Puerto Rico, the cyclone's remnants produced heavy rainfall, peaking at 7.58 in (192.5 mm), that triggered flooding in several regions.
Meteorological history
Tropical Storm Erika originated from a 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...
accompanied by disorganized shower and thunderstorm activity
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...
that moved off the west coast of Africa, near the Cape Verde Islands, on August 25. The following day, 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...
surrounding the wave began to show signs of organization as it tracked westward across the Atlantic. By August 28, an area of low pressure
Low pressure area
A low-pressure area, or "low", is a region where the atmospheric pressure at sea level is below that of surrounding locations. Low-pressure systems form under areas of wind divergence which occur in upper levels of the troposphere. The formation process of a low-pressure area is known as...
developed from the wave. Environmental conditions ahead of the low were favorable for further development of the system. Despite the favorable conditions, the low became increasingly disorganized on August 29, with little convection remaining around the center of circulation. The next day, the system quickly became organized, with shower and thunderstorms developing around the center and 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...
(NHC) noted that the low would likely become a tropical depression within 24 hours. Although convection was well-organized, the system lacked a defined low-level circulation center, leading to the NHC not issuing advisories on the system at that time.
On September 1, a Hurricane Hunter reconnaissance mission into the low found a closed circulation center and tropical storm-force winds. Upon fiding the low-level circulation center, the NHC began monitoring the system as Tropical Storm Erika, the fifth named storm of the 2009 season. Erika was slightly disorganized due to moderate 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...
, with the center partially devoid of convection. However, with warm 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...
s, the storm was forecast to intensify to a strong tropical storm within a few days. A mid-level ridge
Ridge (meteorology)
A ridge is an elongated region of relatively high atmospheric pressure, the opposite of a trough....
to the north led to Erika maintaining a general westward track for most of its existence. Several hours after being classified, the storm reached its peak intensity with winds of 50 mph (85 km/h) and a barometric pressure of 1004 mbar (hPa; 29.65 inHg). However, the peak intensity was operationally placed at 60 mph (95 km/h) based on readings from reconnaissance missions. In post-storm analysis of these readings, it was determined that the NHC had over estimated the wind speeds in an area of unusually heavy rains. By the morning of September 2, Erika became significantly disorganized, and Hurricane Hunters reported the possibility that multiple circulation centers existed within the broader storm system.
Wind shear began to increase earlier than forecast models anticipated, causing the storm to weaken into a minimal tropical storm later that morning. Around 1830 UTC
Coordinated Universal Time
Coordinated Universal Time is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich Mean Time. Computer servers, online services and other entities that rely on having a universally accepted time use UTC for that purpose...
, the center of Erika passed over the island of Guadeloupe
Guadeloupe
Guadeloupe is an archipelago located in the Leeward Islands, in the Lesser Antilles, with a land area of 1,628 square kilometres and a population of 400,000. It is the first overseas region of France, consisting of a single overseas department. As with the other overseas departments, Guadeloupe...
with winds of 40 mph (65 km/h) as the storm entered the eastern Caribbean Sea
Caribbean Sea
The Caribbean Sea is a sea of the Atlantic Ocean located in the tropics of the Western hemisphere. It is bounded by Mexico and Central America to the west and southwest, to the north by the Greater Antilles, and to the east by the Lesser Antilles....
. The circulation later became elongated and began to degenerate into a trough of low pressure
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...
. The NHC noted that due to the large size of the overall system, the center of Erika could reform elsewhere and restrengthen. Following a brief increase in convective activity, the storm slightly intensified before succumbing to wind shear once more. By the afternoon of September 3, the center of Erika was fully devoid of convection and the NHC downgraded it to a tropical depression. Shortly after, the system degenerated into a remnant low, coinciding with the issuance of the final advisory from the NHC. The following day, the remnants approached the southern coast of Puerto Rico, producing heavy rainfall across the island. The system was last noted later on September 4 as it dissipated roughly 80 mi (140 km) south of Puerto Rico.
Preparations
Upon the declaration of Tropical Storm Erika on September 1, tropical storm 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 St. Maarten, Antigua
Antigua
Antigua , also known as Waladli, is an island in the West Indies, in the Leeward Islands in the Caribbean region, the main island of the country of Antigua and Barbuda. Antigua means "ancient" in Spanish and was named by Christopher Columbus after an icon in Seville Cathedral, Santa Maria de la...
, Barbuda
Barbuda
Barbuda is an island in the Eastern Caribbean, and forms part of the state of Antigua and Barbuda. It has a population of about 1,500, most of whom live in the town of Codrington.-Location:...
, St. Kitts, Nevis
Nevis
Nevis is an island in the Caribbean Sea, located near the northern end of the Lesser Antilles archipelago, about 350 km east-southeast of Puerto Rico and 80 km west of Antigua. The 93 km² island is part of the inner arc of the Leeward Islands chain of the West Indies...
, Anguilla
Anguilla
Anguilla is a British overseas territory and overseas territory of the European Union in the Caribbean. It is one of the most northerly of the Leeward Islands in the Lesser Antilles, lying east of Puerto Rico and the Virgin Islands and directly north of Saint Martin...
, St. Martin and Saint Barthélemy
Saint Barthélemy
Saint Barthélemy , officially the Territorial collectivity of Saint Barthélemy , is an overseas collectivity of France. Often abbreviated to Saint-Barth in French, or St. Barts in English, the indigenous people called the island Ouanalao...
. The following day, all of the watches were upgraded to tropical storm warnings as Erika neared 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...
. When the storm entered the Caribbean Sea, a tropical storm warning was issued for Dominica
Dominica
Dominica , officially the Commonwealth of Dominica, is an island nation in the Lesser Antilles region of the Caribbean Sea, south-southeast of Guadeloupe and northwest of Martinique. Its size is and the highest point in the country is Morne Diablotins, which has an elevation of . The Commonwealth...
and tropical storm watches were for Puerto Rico
Puerto Rico
Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
, the U.S. Virgin Islands and the British Virgin Islands
British Virgin Islands
The Virgin Islands, often called the British Virgin Islands , is a British overseas territory and overseas territory of the European Union, located in the Caribbean to the east of Puerto Rico. The islands make up part of the Virgin Islands archipelago, the remaining islands constituting the U.S...
. Early on September 3, the tropical storm watches were upgraded to warnings as Erika drifted through the eastern Caribbean. Later that day, the warnings for Dominica and Guadeloupe were discontinued. Shortly thereafter, all remaining warnings were canceled.
Exports from the Hovensa oil refinery in St. Croix, with a daily production of roughly 500000 barrels (79,493.6 m³), were canceled as ports across the island were closed. All businesses were shut down in Dominica on September 3 due to the storm. In Antigua and Barbuda, all schools and the local airport were closed as a precautionary measure. Two cruise ships, the Carnival Glory
Carnival Glory
Carnival Glory is a Conquest-class cruise ship that was built by Fincantieri in Monfalcone, Italy. She is owned by Carnival Corporation & plc and operated by Carnival Cruise Lines.- Characteristics :...
and a Royal Caribbean
Royal Caribbean International
Royal Caribbean International is a Norwegian and American cruise line brand based in Miami, Florida and owned by Royal Caribbean Cruises Ltd.. With 42 ships in service under 5 different brands and one more under construction, it controls a 25.6% share of the world cruise market...
ship postponed their docking dates and stayed at sea for a few additional days. The islands of Saint Martin and Saint Barthélemy were placed under an orange alert, the second-lowest alert level, and Guadeloupe was placed under a yellow alert, the lowest alert level. In Puerto Rico, officials closed schools and government offices on September 4 and opened 433 shelters across the island. Officials in the Dominican Republic placed nine provinces under warnings as a precautionary measure. Nearby Haiti
Haiti
Haiti , officially the Republic of Haiti , is a Caribbean country. It occupies the western, smaller portion of the island of Hispaniola, in the Greater Antillean archipelago, which it shares with the Dominican Republic. Ayiti was the indigenous Taíno or Amerindian name for the island...
was also alerted of the possibility of heavy rains.
Impact
On September 3, all governmental buildings in Dominica were closed due to flooding triggered by heavy rain from Erika. Landslides were reported in Petite Savanne resulting in road closures. In Guadeloupe, heavy rainfall from Erika, exceeding 7.9 in (200.7 mm) in several areas, produced flooding in Côte-sous-le-Vent. The most significant rain was recorded on La DésiradeLa Désirade
La Désirade is a French West Indies island located at the eastern of Guadeloupe, in the Lesser Antilles.It has a land area of 20.64 km² and a population of 1,595 in 2006 , with a population density of 77 inh. per km² in 2006...
at 12.1 in (307.3 mm), of which a record 9.4 in (238.8 mm) fell in 24 hours. Sustained winds reached 56 mph (90 km/h) on the island of Marie Galante. One rock slide occurred near Losteau, in Bouillante. Several roads became impassable due to flood waters. At the height of the storm, an estimated 12,000 people were without power across the island. Up to 5.5 in (139.7 mm) of rain fell along the foothills in Trinidad
Trinidad
Trinidad is the larger and more populous of the two major islands and numerous landforms which make up the island nation of Trinidad and Tobago. It is the southernmost island in the Caribbean and lies just off the northeastern coast of Venezuela. With an area of it is also the fifth largest in...
. In St. Martin, a peak of 3.7 in (94 mm) of rain fell. In the United States Virgin Islands
United States Virgin Islands
The Virgin Islands of the United States are a group of islands in the Caribbean that are an insular area of the United States. The islands are geographically part of the Virgin Islands archipelago and are located in the Leeward Islands of the Lesser Antilles.The U.S...
, up to 1.61 in (40.9 mm) of rain fell in a 24 hour span, resulting in minor flooding.
In Puerto Rico, the remnants of Erika produced significant amounts of rainfall, causing the rivers of La Plata, Loíza, and Caguitas to overflow their banks and trigger widespread flooding. A weather station in Naguabo recorded 7.92 in (201.2 mm) of precipitation. Several other areas recorded upwards of 4 in (101.6 mm). In the municipality of Guanica, several homes were flooded, leaving $5,000 in damage. The most severe damage took place in the municipality of Las Piedras where $15,000 was reported in flood losses. One river rose to a level of 29.27 ft (8.9 m), 7.27 ft (2.2 m) above flood stage. Damage in Fajardo was estimated at $10,000 after homes were inundated by flood waters. Additionally, flooding in Caguas resulted in $5,000 in damage. In the Dominican Republic flood warnings were issued for the provinces of La Altagracia, El Seibo, Hato Mayor, Monte Plata, Samana, Duarte and Maria Trinidad Sanchez due the threat of continued rainfall and flooding.
See also
- 2009 Atlantic hurricane season2009 Atlantic hurricane seasonThe 2009 Atlantic hurricane season was a below-average year, unlike the 2009 Pacific hurricane season, which was above average, both due to a moderate El Niño. During this year, nine tropical storms formed, the fewest since the 1997 season.An average season has ten tropical storms, six hurricanes...
- Timeline of the 2009 Atlantic hurricane seasonTimeline of the 2009 Atlantic hurricane seasonThe 2009 Atlantic hurricane season was a below-average year in which nine tropical storms formed, the fewest since 1997.An average season has eleven tropical storms, six hurricanes and two major hurricanes. Although Tropical Depression One formed on May 28, 2009, the season officially began on...
- List of storms in the 2009 Atlantic hurricane season