Tropical Depression Four-C (2006)

Infobox Hurricane
Name=Tropical Depression Four-C
Type=Tropical depression
Year=2006
Basin=EPac
Image location=TD 4C 13 oct 2006 2143Z.jpg


Formed=October 13, 2006
Dissipated=October 14, 2006
1-min winds=30
Pressure=1007
Da

Inflated=
Fatalities=None reported
Areas=Hawaii
Hurricane season=2006 Pacific hurricane season

Tropical Depression Four-C was a short-lived tropical depression the 2006 Pacific hurricane season. The depression formed from from a persistent low-pressure area south of Oahu on October 13, 2006. The depression did not last long, dissipating from upper-level wind shear on October 14. The remains of the depression caused heavy rainfall and thunderstorms on October 17 in Big Island. The depression proved difficult for the Central Pacific Hurricane Center to forecast. After the depression had dissipated, the system, along with a cold front also affected the island of Maui.

Meteorological history

Tropical Depression Four-C formed from a persistant low-pressure area on October 13 at 1500 UTC. The depression formed from several days of slow development. The depression had registered winds of 40 mph (60 km/h) north of the system's center. The system remained mainly stationary within an unusual steering flow was on top of Tropical Depression Four-C. This steering flow eventually progressed the system slowly to the southwest. The hurricane center predicted that the storm would not strengthen any further than what it started with, 35 mph (55 km/h).cite web|url=http://www.prh.noaa.gov/cphc/tcpages/archive/2006/TCDCP5.CP042006.1.0610132051|publisher=Central Pacific Hurricane Center|author=Andy Nash|title=Tropical Depression Four-C Discussion 1|accessdate=2008-09-06|date=October 13, 2006] Six hours later, when the next advisory had come out, the depression retained its strength of a tropical depression. However, the stationary system was beginning to move to the east, a rare occurrence. Wind shear increased by the evening of October 13, starting to pull the system apart.cite web|url=http://www.prh.noaa.gov/cphc/tcpages/archive/2006/TCDCP5.CP042006.2.0610140245|publisher=Central Pacific Hurricane Center|author=Andy Nash|title=Tropical Depression Four-C Discussion 2|accessdate=2008-09-06|date=October 13, 2006]

The depression continued to survive, causing forecasting difficulty. The forecast changed by the night of the 13th. QuikScat runs missed the depression, and the hurricane center defied the models that were showing a well-defined center. The forecaster instead kept the depression at the same strength of 35 mph (55 km/h). However, the shear had already done its damage as the radar showed the system falling apart.cite web|url=http://www.prh.noaa.gov/cphc/tcpages/archive/2006/TCDCP5.CP042006.3.0610140910|publisher=Central Pacific Hurricane Center|author=Donaldson|title=Tropical Depression Four-C Discussion 3|accessdate=2008-09-06|date=October 13, 2006] The depression however, did not survive the strong shear, eventually turning into a low-level circulation center. The depression had been sheared apart so badly in the 24 hours it had survived, the hurricane center ceased advisories on the depression and foretasted that it would not survive much after that. People were still advised to watch the system as it still posed a threat to the Hawaiian Islands.cite web|url=http://www.prh.noaa.gov/cphc/tcpages/archive/2006/TCDCP5.CP042006.4.0610141440|publisher=Central Pacific Hurricane Center|author=Donaldson|title=Tropical Depression Four-C Discussion 4|accessdate=2008-09-06|date=October 14, 2006] The depression became a low-level swirl of clouds and moisture, moving to the northeast into a trough. This trough brought the system to the Big Island of Hawaii, and three days later, the remains affected Hawaii.cite web|url=http://www.prh.noaa.gov/cphc/summaries/2006.php#td04c|publisher=Central Pacific Hurricane Center|author=Andy Nash et al.|title=Tropical Depression Four-C Tropical Cyclone Report|accessdate=2008-09-06|date=July 2007]

Preparations and impact

On October 14, as the shearing system approached Hawaii, the state's government issued a flash flood warning for the islands. The hurricane center had predicted that the system would bring heavy rainfall, strong thunderstorms and flooding to the islands.cite web|url=http://www.fema.gov/emergency/reports/2006/nat101406.shtm|title=National Situation Update: Saturday, October 14, 2006|publisher=Federal Emergency Management Agency|accessdate=2008-09-06|date=October 14, 2006] On October 16, the National Weather Service issued a flash flood warning for the island of Maui. At around 1800 UTC, the remains of Tropical Depression Four-C and a nearby cold front were already causing rainfall in parts of the island. With waters in rivers already rising, the warning was extended, with the predictions that mudslides could occur along with flooding. They also warned that people should evacuate to higher grounds due to the flooding.cite web|url=http://www.kitv.com/weather/10088083/detail.html|title=Flash Flood Warning Issued for Maui|author=Ben Gutierrez|publisher=KITV-4, Honolulu|accessdate=2008-09-06|date=October 16, 2006]

On October 17, the remains of the depression did pass over the island of Hawaii, causing heavy rainfall and flooding to the island. No damage total or fatalities were reported from the remains of the tropical depression.

See also

*Tropical cyclone
*2006 Pacific hurricane season

References

External links

* [http://www.prh.noaa.gov/cphc/tcpages/archive.php?stormid=CP042006 Advisory Archive of Tropical Depression Four-C by the Central Pacific Hurricane Center]