Tropical Storm Erick (2007)

Infobox Hurricane
Name=Tropical Storm Erick
Type=Tropical storm
Year=2007
Basin=EPac
Image location=Erick 01 aug 2007 1825Z.jpg


Formed=July 31, 2007
Dissipated=August 2, 2007
1-min winds=35
Pressure=1004
Da

Fatalities=None reported
Areas=No land areas
Hurricane season=2007 Pacific hurricane season

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 next day, the depression intensified into a tropical storm, and received the name "Erick" while continuing its westward track. However, the shear did not allow the storm to gain more strength, and broke up the storm's structure within a matter of days. The cyclone weakened to a tropical depression on August 2 and degenerated into a remnant low shortly after. Because the storm never neared land, no damage was reported in association with Erick.

Meteorological history

On July 16, 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 Antilles with some deep, yet disorganized thunderstorm activity. The wave crossed Central America three days later and entered the Eastern Pacific Ocean, where it spawned a small low pressure area on July 28. Wind shear prevented tropical cyclone development for a few days, leaving the area of atmospheric convection, or thunderstorms, separated from the low. On July 31, the convection formed closer to the center of the storm, and the system had become sufficiently organized to be designated as a tropical depression at 1200 UTC. At this time the system—designated as Tropical Depression Eight-E by Miami's National Hurricane Center—was located 1,060 miles (1,700 km) southwest of the southern tip of Baja California.cite web|author=Eric S. Blake|title=Tropical Storm Erick Tropical Cyclone Report|date=August 23, 2007|publisher=National Hurricane Center|accessdate=2008-09-06|url=http://www.nhc.noaa.gov/pdf/TCR-EP082007_Erick.pdf|format=PDF]

The convection remained concentrated on the western edge of the storm due to the shear and the presence of dry air. [cite web|author=Avila|title=Tropical Depression Eight-E Discussion Number 1|date=July 31, 2007|publisher=National Hurricane Center|accessdate=2008-09-06|url=http://www.nhc.noaa.gov/archive/2007/ep08/ep082007.discus.001.shtml?] Dvorak intensity estimates showed that the storm's winds picked up speed, so the depression was upgraded to a tropical storm, and given the name "Erick" twelve hours later, at 0000 UTC on August 1.cite web|author=Avila|date=August 1, 2007|title=Tropical Storm Erick discussion #2|publisher=National Hurricane Center|accessdate=2007-08-01|url=http://www.nhc.noaa.gov/archive/2007/ep08/ep082007.discus.002.shtml?] [cite web|author=Staff Writer|title=Tropical Storm Erick forms in Pacific.|date=August 1, 2007|publisher=MSNBC|accessdate=2008-09-17|url=http://www.msnbc.msn.com/id/20067595/] [cite web|author=Associated Press|title=Tropical Storm Erick Forms In Pacific|date=August 1, 2007|publisher=CBS News|accessdate=2008-09-17|url=http://www.cbsnews.com/stories/2007/08/01/storm/main3122535.shtml] At the time of its upgrade, Erick attained peak winds of 40 mph (65 km/h) and a minimum central pressure of 1005 mbar (29.68 inHg). The wind shear never relented, and the cyclone maintained a disorganized structure with a lack of banding features. Although finding the exact position of the center of circulation was difficult, it was estimated 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. [cite web|author=Pasch|title=Tropical Storm Erick Discussion Number 3|date=August 1, 2007|publisher=National Hurricane Center|accessdate=2008-09-06|url=http://www.nhc.noaa.gov/archive/2007/ep08/ep082007.discus.003.shtml?] Later on August 1, the strong shear separated the center from the waning area of thunderstorm activity, indicating that the storm was deteriorating.cite web|author=Rhome|title=Tropical Storm Erick Discussion Number 5|date=August 1, 2007|publisher=National Hurricane Center|accessdate=2008-09-06|url=http://www.nhc.noaa.gov/archive/2007/ep08/ep082007.discus.005.shtml?] Erick weakened back to a tropical depression at 0000 UTC on August 2, only 24 hours after it had become a tropical storm.

The low-level center then became elongated and ill-defined; [cite web|author=Brown|title=Tropical Storm Erick Discussion Number 5|date=August 2, 2007|publisher=National Hurricane Center|accessdate=2008-09-06|url=http://www.nhc.noaa.gov/archive/2007/ep08/ep082007.discus.006.shtml?] the depression continued weakening quickly, and it had degenerated back into a tropical wave by 0600 UTC on August 2, thousands of miles away from land. [cite web|author=Associated Press|title=Tropical Storm Erick weakens far off Mexico's Pacific coast|year=2007|publisher="Union-Tribune"|accessdate=2008-09-18|url=http://www.signonsandiego.com/news/mexico/20070802-0958-mexico-tropicalweather.html] A weak low pressure system formed along the wave on August 3, although it failed to reorganize as it entered the North Pacific. On August 5, the low-level remnants of Tropical Storm Erick passed south of Hawaii, though caused no effects. [cite web|author=Honolulu National Weather Service|title=August 2007 Precipitation Summary|year=2007|publisher=NOAA|accessdate=2008-09-24|url=http://www.prh.noaa.gov/hnl/hydro/pages/aug07sum.php] The low dissipated fully on August 8. In terms of forecasting, despite lower than average official forecast errors, Erick was poorly forecast. The storm formed without significant previous warning, and dissipated similarly.

Impact and statistics

Because Erick remained away from land, no effects, property damage or fatalities were reported; no ships were affected, and no tropical cyclone warnings and watches were issued. According to the National Climatic Data Center, Tropical Storm Erick had an Accumulated Cyclone Energy (ACE) of 0.8575. This value—an approximation of the kinetic energy used by a tropical system throughout its existence—was the second lowest of the season, just slightly larger than Tropical Storm Alvin's ACE of 0.6125. [cite web|author=National Climatic Data Center|title=2007 Eastern North Pacific Ocean Tropical Cyclones|year=2007|publisher=NCDC|accessdate=2008-09-18|url=http://www.ncdc.noaa.gov/oa/climate/research/2007/2007-ne-pacific-trop-cyclones.html] Due to the lack of any impact, the name "Erick" was not retired, and is scheduled to be reused for the fifth named storm of the 2013 Pacific hurricane season. Eastern North Pacific naming follows the same scheme as the North Atlantic, but with its own lists. The present naming system was introduced a year earlier than the Atlantic system, when List IV was used anomalously in 1978, but List I was used in 1979 in parallel with that in the Atlantic.cite web|title=Worldwide Tropical Cyclone Names|year=2007|publisher=National Hurricane Center|accessdate=2008-09-13|url=http://www.nhc.noaa.gov/aboutnames.shtml]

ee also

*List of Pacific hurricanes
*
*2007 Pacific hurricane season

References