:Cyclone Arthur (2007)

{{storm path|Arthur 2007 track.png}}

During January 21, 2007, the Fiji Meteorological Service (FMS) reported that Tropical Depression 08F had developed about {{convert|435|km|mi|round=5|abbr=on}} to the west-northwest of Savai'i in Samoa.{{cite report|date=December 8, 2008|access-date=August 30, 2015|title=Tropical Cyclone Seasonal Summary 2006-07|author=RSMC Nadi — Tropical Cyclone Centre|publisher=Fiji Meteorological Service|url=https://www.wmo.int/pages/prog/www/tcp/Best%20Tracks/documents/TCSeasonalSummary06-07.doc}}{{cite web|author=Gary Padgett|publisher=Typhoon 2000|date=March 28, 2007|access-date=February 21, 2007|title=Monthly Tropical Weather Summary for January 2007|url=http://www.typhoon2000.ph/garyp_mgtcs/jan07sum.htm}} The depression slowly traveled towards the east-southeast for several days as the overall structure of the storm fluctuated due to diurnal variations and strong wind shear. Around 1700 UTC on January 22, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert for the depression. The system developed a large banding feature in the northern portion of the circulation and deep convection formed around the center of circulation. The depression had moved into an area of weak to moderate wind shear with favorable diffulence aloft.{{cite web|publisher=Unisys Corporation|date=January 22, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 22, 2007 at 12Z|url=http://www.weather.unisys.com/hurricane/archive/07012212|archive-url=https://web.archive.org/web/20071029170721/http://weather.unisys.com/hurricane/archive/07012212|archive-date=October 29, 2007|url-status=dead}} Later that day, gale warnings were issued for the northeastern quadrant of the system. Tropical Depression 08F continued to develop as an anticyclone developed above the system, enhancing the environment around it. A mid-latitude trough located north of the depression was steering it towards the east.{{cite web|publisher=Unisys Corporation|date=January 22, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 22, 2007 at 18Z|url=http://www.weather.unisys.com/hurricane/archive/07012218|archive-url=https://web.archive.org/web/20071029174750/http://weather.unisys.com/hurricane/archive/07012218|archive-date=October 29, 2007|url-status=dead}}

Early on January 24, the system became better organized and strengthened into a cyclone at 0600 UTC. The storm, which was named Arthur by the FMS, began to undergo rapid intensification as the structure improved significantly. Deep convection developed around the center with strong outflow towards the north. Several hours after becoming a cyclone, the JTWC issued their first advisory on Tropical Cyclone 09P as it traveled quickly towards the east-southeast. The quick movement was due to the influences of subtropical ridge to the north and a trough to the south.{{cite web|publisher=Unisys Corporation|date=January 24, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 24, 2007 at 12Z|url=http://www.weather.unisys.com/hurricane/archive/07012412|archive-url=https://web.archive.org/web/20071029174805/http://weather.unisys.com/hurricane/archive/07012412|archive-date=October 29, 2007|url-status=dead}} Later that day, a banding eye feature began to develop as the storm intensified into a Category 2 cyclone on the Australian intensity scale.{{cite web|publisher=Unisys Corporation|date=January 24, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 24, 2007 at 18Z|url=http://www.weather.unisys.com/hurricane/archive/07012418|archive-url=https://web.archive.org/web/20071029174810/http://weather.unisys.com/hurricane/archive/07012418|archive-date=October 29, 2007|url-status=dead}} At 1800 UTC, the JTWC assessed Arthur to have reached its peak intensity with winds of {{convert|120|km/h|mph|abbr=on}} 1-minute winds), the equivalent of a minimal Category 1 hurricane on the Saffir–Simpson scale.{{cite web|publisher=Joint Typhoon Warning Center|year=2008|access-date=February 21, 2009|title=JTWC Best Track for Tropical Cyclone 09P (Arthur)|url=http://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/best_tracks/2007/2007s-bsh/bsh092007.txt|archive-date=March 4, 2010|archive-url=https://web.archive.org/web/20100304055353/http://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/best_tracks/2007/2007s-bsh/bsh092007.txt|url-status=dead}} Early on January 25, Arthur reached its peak intensity with winds of {{convert|110|km/h|mph|abbr=on}} 10-minute winds) with a minimum pressure of 975 hPa (mbar) while located about {{convert|635|km|mi|abbr=on}} north-northwest of Rarotonga. Shortly after peaking in intensity, Arthur began to undergo an extratropical transition and rapidly deteriorated{{cite web|publisher=Unisys Corporation|date=January 25, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 25, 2007 at 00Z|url=http://www.weather.unisys.com/hurricane/archive/07012500|archive-url=https://web.archive.org/web/20071029182901/http://weather.unisys.com/hurricane/archive/07012500|archive-date=October 29, 2007|url-status=dead}} due to strong wind shear.

File:Arthur 2007 regenerated 12607.jpg

The storm also began to merge with a low-level frontal boundary associated with the remnants of Tropical Cyclone Zita. The strong shear left the center of circulation partially exposed, with deep convection persisting in only the southeastern quadrant.{{cite web|publisher=Unisys Corporation|date=January 25, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 25, 2007 at 06Z|url=http://www.weather.unisys.com/hurricane/archive/07012506|archive-url=https://web.archive.org/web/20071029170736/http://weather.unisys.com/hurricane/archive/07012506|archive-date=October 29, 2007|url-status=dead}} In addition to the shear, dry air began to enter the system, causing it to weaken further.{{cite web|publisher=Unisys Corporation|date=January 25, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 25, 2007 at 12Z|url=http://www.weather.unisys.com/hurricane/archive/07012512|archive-url=https://web.archive.org/web/20071029174816/http://weather.unisys.com/hurricane/archive/07012512|archive-date=October 29, 2007|url-status=dead}} While continuing to move at a quick pace, the storm began to turn towards the southeast along a baroclinic zone. Early on January 26, the JTWC issued their final advisory on the cyclone as it lost most of its tropical characteristics.{{cite web|publisher=Unisys Corporation|date=January 26, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 26, 2007 at 00Z|url=http://www.weather.unisys.com/hurricane/archive/07012600|archive-url=https://web.archive.org/web/20071029174821/http://weather.unisys.com/hurricane/archive/07012600|archive-date=October 29, 2007|url-status=dead}} Arthur re-intensified shortly after{{cite web|publisher=Unisys Corporation|date=January 26, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 26, 2007 at 06Z|url=http://www.weather.unisys.com/hurricane/archive/07012606|archive-url=https://web.archive.org/web/20071029182906/http://weather.unisys.com/hurricane/archive/07012606|archive-date=October 29, 2007|url-status=dead}} and the JTWC reissued advisories on the storm around 2100 UTC. The brief re-strengthening was the result of a breakdown in the baroclinic zone which allowed convection to redevelop around the center.{{cite web|publisher=Unisys Corporation|date=January 27, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 27, 2007 at 00Z|url=http://www.weather.unisys.com/hurricane/archive/07012700|archive-url=https://web.archive.org/web/20071029182916/http://weather.unisys.com/hurricane/archive/07012700|archive-date=October 29, 2007|url-status=dead}} Around the same time, Arthur left the FMS's area of responsibility (AoR) and entered the New Zealand's MetService's AoR. The storm completed its extratropical transition around 1200 UTC on January 27, leading to the final advisory being issued on the storm.

On January 21, a gale watch was issued for Tutuila, American Samoa, Manu'a, and Swains Island as Tropical Depression 08F approached the islands. Winds of up to {{convert|55|km/h|mph|abbr=on}}, with gusts up to {{convert|75|km/h|mph|abbr=on}}, were expected.{{cite web|publisher=Unisys Corporation|date=January 22, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 22, 2007 at 00Z|url=http://www.weather.unisys.com/hurricane/archive/07012200|archive-url=https://web.archive.org/web/20071029174740/http://weather.unisys.com/hurricane/archive/07012200|archive-date=October 29, 2007|url-status=dead}} Small craft advisories were issued for the Cook Islands due to large swells produced by the storm. All of the watches were cancelled late on January 23 as the depression was no longer forecast to impact the islands.{{cite web|publisher=Unisys Corporation|date=January 23, 2007|access-date=February 21, 2009|title=TCWC Advisories for January 23, 2007 at 18Z|url=http://www.weather.unisys.com/hurricane/archive/07012318|archive-url=https://web.archive.org/web/20071029182856/http://weather.unisys.com/hurricane/archive/07012318|archive-date=October 29, 2007|url-status=dead}} On January 24, an Orange Alert was issued for the Austral Islands. As the storm neared the region, the alert was upgraded to a Red Alert for Rurutu and Tubuai.{{cite web|author=French Polynesia|publisher=World Meteorological Organization|date=July 17, 2008|access-date=February 21, 2009|title=Review of the 2006/2007 and 2007/2008 Tropical Cyclone Seasons|url=http://www.wmo.int/pages/prog/www/tcp/Meetings/RA%20V%20TCC-12/documents/Doc_05-2.doc}} Arthur produced minor damages in the Cook Islands—primarily consisting of beach erosion—on January 24.{{cite web|author=Kevin Vang|publisher=Asia-Pacific Disaster Alerts|date=January 26, 2007|access-date=February 21, 2009|title=Cyclone Arthur passing between Southern Cooks and Western French Polynesia|url=http://www.afap.org/apcedi/2007/01/apcedi-alert-spci-09p-arthur-2-2007.html|archive-url=https://web.archive.org/web/20070830032318/http://www.afap.org/apcedi/2007/01/apcedi-alert-spci-09p-arthur-2-2007.html|archive-date=August 30, 2007}} Heavy rains throughout French Polynesia resulted in several landslides which damaged several homes on Tahiti and Moorea. Waves near the islands ranged from {{convert|1.5|to|2|m|ft|abbr=on}}.{{cite web|author=Kevin Vang|publisher=Asia-Pacific Disaster Alerts|date=January 25, 2007|access-date=February 21, 2009|title=Cyclone Arthur forms near Southern Cooks as Cyclone Zita exits French Polynesia|url=http://www.afap.org/apcedi/2007/01/apcedi-alert-spci-09p-arthur-1-2007.html|archive-url=https://web.archive.org/web/20070813114628/http://www.afap.org/apcedi/2007/01/apcedi-alert-spci-09p-arthur-1-2007.html|archive-date=August 13, 2007}} Winds in Tubuai reached {{convert|85|km/h|mph|abbr=on}} 10-minute winds) with gusts up to {{convert|115|km/h|mph|abbr=on}}. Several homes were damaged and roads were blocked by fallen trees throughout the island. Minor coastal flooding also occurred due to the large swells.{{cite web|author=Ashmita Gosai and Stuart Burgess|publisher=National Institute of Water & Atmospheric Research|url=http://www.wamis.org/countries/southpac/spacClimate200706.pdf|date=June 2007|access-date=February 21, 2009|title=The Island Climate Update|archive-date=February 25, 2009|archive-url=https://web.archive.org/web/20090225022527/http://www.wamis.org/countries/southpac/spacClimate200706.pdf|url-status=dead}}

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