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Tropical Storm Erick (2007)
Encyclopedia
Tropical Storm Erick was the eighth tropical cyclone
of the 2007 Pacific hurricane season
, and the fifth to attain tropical storm status. Erick originated from a tropical wave
that moved off the coast of Africa
, traveled westward across the Atlantic
, and emerged into the Eastern Pacific Ocean
without any further development
. The wave spawned a small low-pressure system
on July 28, which matured into a tropical depression later that day despite strong wind shear
in the region. The depression intensified into a tropical storm, and received the name
"Erick" while continuing its westward track. However, the shear prevented the storm from intensifying further, and broke up the storm's structure within a few days. The cyclone weakened to a tropical depression
and degenerated into a remnant low shortly after. Because the storm remained far out at sea, no damage was reported in association with Erick.
with some strong, yet disorganized thunderstorm
activity. The wave crossed Central America
three days later and entered the Eastern Pacific Ocean, where it later spawned a small low pressure area
. Wind shear
prevented tropical cyclone development
for a few days, leaving the area of atmospheric convection
, or thunderstorms, separated from the low. The convection began to form closer to the center of the storm, and the system had become sufficiently organized to be designated as Tropical Depression Eight-E by Miami
's National Hurricane Center
on July 31. At the time the depression was located 1,060 miles (1,700 km) southwest of the southern tip of Baja California
.
The convection remained concentrated on the western edge of the storm because of the shear and the presence of dry air. Dvorak intensity estimates
showed that the storm's winds had accelerated, so the depression was upgraded to a tropical storm, and given the name "Erick" twelve hours later, at 0000 UTC on August 1; it became the fifth named storm of the 2007 Pacific hurricane season. At the time of its upgrade, Erick attained its peak winds of 40 mph (65 km/h) and a minimum central pressure of 1004 mbar
(hPa; 29.66 inHg
). The wind shear did not relent, and the cyclone maintained a disorganized structure with a lack of banding features. Although the exact position of the center of circulation was difficult for forecasters to establish, it was estimated that the storm was tracking westward at around 10 mph (17 km/h) under the steering currents of a mid-level ridge
located to the north of the system. Later on August 1, the strong shear separated the center from the waning area of thunderstorm activity, indicating that the storm was deteriorating. Erick weakened back to a tropical depression on August 2, only 24 hours after it had become a tropical storm.
The low-level center then became elongated and ill-defined; the depression continued to weaken quickly, and it had degenerated back into a tropical wave on August 2, thousands of miles from land. A weak low pressure system formed along the wave, although it did not reorganize into a tropical cyclone as it entered the North Central Pacific. On August 5, the low-level remnants of Tropical Storm Erick passed south of Hawaii
, although they caused no effects on the islands. The low dissipated fully on August 8. According to the storm's Tropical Cyclone Report, the National Hurricane Center considered that it had poorly forecast Erick's evolution. In particular, the storm formed without significant warning, and dissipated similarly.
were issued. Throughout its course, Erick posed a threat only to shipping lanes.
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...
of the 2007 Pacific hurricane season
2007 Pacific hurricane season
The 2007 Pacific hurricane season was an event in the annual cycle of tropical cyclone formation. It officially started on May 15, 2007 in the eastern Pacific, designated as the area east of 140°W, and on June 1, 2007 in the central Pacific, which is between the International Date Line and 140°W,...
, and the fifth to attain tropical storm status. Erick originated from 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...
that moved off the coast of Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, traveled westward across the Atlantic
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...
, and emerged into the Eastern Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
without any further development
Tropical cyclogenesis
Tropical cyclogenesis is the term that describes the development and strengthening of a tropical cyclone in the atmosphere. The mechanisms through which tropical cyclogenesis occurs are distinctly different from those through which mid-latitude cyclogenesis occurs...
. The wave spawned a small low-pressure system
Pressure system
A pressure system is a region of the Earth's atmosphere where air pressure is a relative peak or lull in the sea level pressure distribution. The surface pressure at sea level varies minimally, with the lowest value measured and the highest recorded...
on July 28, which matured into a tropical depression later that day despite strong 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...
in the region. The depression intensified into a tropical storm, and received the name
Tropical cyclone naming
Tropical cyclones have officially been named since 1945 and are named for a variety of reasons, which include to facilitate communications between forecasters and the public when forecasts, watches, and warnings are issued. Names also reduce confusion about what storm is being described, as more...
"Erick" while continuing its westward track. However, the shear prevented the storm from intensifying further, and broke up the storm's structure within a few days. The cyclone weakened to a tropical depression
Tropical cyclone scales
Tropical systems are officially ranked on one of several tropical cyclone scales according to their maximum sustained winds and in what oceanic basin they are located...
and degenerated into a remnant low shortly after. Because the storm remained far out at sea, no damage was reported in association with Erick.
Meteorological history
In the middle of July 2007, a tropical wave emerged from the coast of Africa and traveled westward across the Atlantic Ocean. On July 22, the wave passed through the Lesser AntillesLesser 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...
with some strong, yet disorganized thunderstorm
Thunderstorm
A thunderstorm, also known as an electrical storm, a lightning storm, thundershower or simply a storm is a form of weather characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere known as thunder. The meteorologically assigned cloud type associated with the...
activity. The wave crossed Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
three days later and entered the Eastern Pacific Ocean, where it later spawned a small low pressure area
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...
. 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...
prevented tropical cyclone development
Tropical cyclogenesis
Tropical cyclogenesis is the term that describes the development and strengthening of a tropical cyclone in the atmosphere. The mechanisms through which tropical cyclogenesis occurs are distinctly different from those through which mid-latitude cyclogenesis occurs...
for a few days, leaving the area of atmospheric 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...
, or thunderstorms, separated from the low. The convection began to form closer to the center of the storm, and the system had become sufficiently organized to be designated as Tropical Depression Eight-E by Miami
Miami, Florida
Miami is a city located on the Atlantic coast in southeastern Florida and the county seat of Miami-Dade County, the most populous county in Florida and the eighth-most populous county in the United States with a population of 2,500,625...
's 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...
on July 31. At the time the depression was located 1,060 miles (1,700 km) southwest of the southern tip of Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
.
The convection remained concentrated on the western edge of the storm because of the shear and the presence of dry air. Dvorak intensity estimates
Dvorak technique
The Dvorak technique is a widely used system to subjectively estimate tropical cyclone intensity based solely on visible and infrared satellite images. Several agencies issue Dvorak intensity numbers for cyclones of sufficient intensity...
showed that the storm's winds had accelerated, so the depression was upgraded to a tropical storm, and given the name "Erick" twelve hours later, at 0000 UTC on August 1; it became the fifth named storm of the 2007 Pacific hurricane season. At the time of its upgrade, Erick attained its peak winds of 40 mph (65 km/h) and a minimum central pressure of 1004 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...
(hPa; 29.66 inHg
Inch of mercury
Inches of mercury, ' is a unit of measurement for pressure. It is still widely used for barometric pressure in weather reports, refrigeration and aviation in the United States, but is seldom used elsewhere....
). The wind shear did not relent, and the cyclone maintained a disorganized structure with a lack of banding features. Although the exact position of the center of circulation was difficult for forecasters to establish, it was estimated that the storm was tracking westward at around 10 mph (17 km/h) under the steering currents of a mid-level ridge
High pressure area
A high-pressure area is a region where the atmospheric pressure at the surface of the planet is greater than its surrounding environment. Winds within high-pressure areas flow outward due to the higher density air near their center and friction with land...
located to the north of the system. Later on August 1, the strong shear separated the center from the waning area of thunderstorm activity, indicating that the storm was deteriorating. Erick weakened back to a tropical depression on August 2, only 24 hours after it had become a tropical storm.
The low-level center then became elongated and ill-defined; the depression continued to weaken quickly, and it had degenerated back into a tropical wave on August 2, thousands of miles from land. A weak low pressure system formed along the wave, although it did not reorganize into a tropical cyclone as it entered the North Central Pacific. On August 5, the low-level remnants of Tropical Storm Erick passed south of Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
, although they caused no effects on the islands. The low dissipated fully on August 8. According to the storm's Tropical Cyclone Report, the National Hurricane Center considered that it had poorly forecast Erick's evolution. In particular, the storm formed without significant warning, and dissipated similarly.
Impact and statistics
Because Erick remained, according to NHC forecaster Richard Pasch, "very far away from everywhere", no effects, property damage or fatalities were reported; no ships recorded tropical storm-force winds, and no tropical cyclone warnings and 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. Throughout its course, Erick posed a threat only to shipping lanes.
See also
- List of Pacific hurricanes
- Other East Pacific tropical storms
- Other storms of the same name
- Timeline of the 2007 Pacific hurricane seasonTimeline of the 2007 Pacific hurricane seasonThe 2007 Pacific hurricane season was an event in the annual cycle of tropical cyclone formation. This timeline documents all the storm formations, strengthening, weakening, landfalls, extratropical transitions, and dissipation...