2006–07 South Pacific cyclone season

2006–07 South Pacific cyclone season
Season summary map
First system formed October 21, 2006
Last system dissipated April 6, 2007
Strongest storm Xavier – 930 hPa (mbar), 175 km/h (110 mph) (10-minute sustained)
Total disturbances 15
Total depressions 12
Tropical cyclones 6
Severe tropical cyclones 2
Total fatalities Unknown
Total damage Unknown
South Pacific tropical cyclone seasons
2004–05, 2005–06, 2006–07, 2007–08, 2008–09
Related articles

The 2006–07 South Pacific cyclone season was an event in the annual cycle of tropical cyclone formation. It began on November 1, 2006 and ended on April 30, 2007. These dates conventionally delimit the period of each year when most tropical cyclones form in the southern Pacific Ocean east of 160°E. Additionally, the regional tropical cyclone operational plan defines a tropical cyclone year separately from a tropical cyclone season, and the "tropical cyclone year" runs from July 1, 2006 to June 30, 2007.[1]

Tropical cyclones between 160°E and 120°W and north of 25°S are monitored by the Fiji Meteorological Service in Nadi. Those that move south of 25°S are monitored by the Tropical Cyclone Warning Centre in Wellington, New Zealand.[1]

Seasonal outlooks

Source
Record 		Tropical
Cyclone 		Severe
Tropical Cyclone 		Ref
Record high: 1997–98:16 1982–83:10 [2]
Record low: 2003–04: 3 1994-95: 1 [2]
Activity during the season 6 2

In September and October 2006, as a weak to moderate El Niño developed across the Pacific ocean, both RSMC Nadi and New Zealand's National Institute of Water and Atmospheric Research reported that the basin would see a significant change in the frequency and distribution of tropical cyclones in the region and beyond. They were expecting that 10 or more tropical cyclones would develop compared to an average of 8 during an average season with the greatest risk being for them to form near to and to the east of the 180th meridian. As a result they reported that Fiji, Tonga, Niue, Samoa and Southern Cook Islands had the greatest risk of being affected by a tropical cyclone while reporting that other islands had an average to below average risk.[3][4]

Seasonal summary

Cyclone Cliff Cyclone Arthur (2007)

The 2006–07 South Pacific cyclone season got off to an early start with a tropical disturbance developing into Cyclone Xavier, late on October 21. Xavier rapidly intensified and became a category three Severe Tropical Cyclone on the Australian tropical cyclone intensity scale during the next day. As a Severe Tropical Cyclone, Xavier passed over Tikopia and then continued to intensify and reached its peak wind speeds early on October 24. Xavier then rapidly weakened during the next day which led to the final advisories being issued on October 26. Whilst Xavier was active, Tropical Depression 02F formed on October 24 to the northeast of American Samoa. As the depression moved towards the west, it remained weak as it was badly affected by Cyclone Xavier's outflow, the final advisory was released on October 29. Early on November 1, Tropical Disturbance 03F formed to the northeast of Fiji. It was then upgraded to a Tropical Depression later that day. The depression then meandered around the International dateline for a couple days without any significant development, with the final advisory being issued by RSMC Nadi early on November 3. Cyclone Yani formed as a weak tropical disturbance on November 16, it was upgraded into Tropical Depression 04F early the next day. Over the next few days the depression moved towards the west gradually developing until a Tropical Cyclone Formation Alert was issued late on November 21. Early the next day it was upgraded to Cyclone Yali by RSMC Nadi and designated as 02P by the JTWC, after being classified Yani started to intensify quite quickly becoming a Category three severe tropical cyclone early on November 23. Yali then reached its peak windspeeds later that day before starting to rapidly weaken early on November 24, as it entered an area of higher wind shear and was downgraded to a Tropical Depression later that day.

Storms

Severe Tropical Cyclone Xavier

Category 4 severe tropical cyclone (Australian scale)
Category 4 tropical cyclone (SSHWS)
Duration October 21 – October 26
Peak intensity 175 km/h (110 mph) (10-min)  930 mbar (hPa)
Main article: Cyclone Xavier

On October 20 a weak tropical disturbance formed to the north of the Santa Cruz Islands.[5] During the next day it rapidly developed and was designated as Tropical Cyclone Xavier whilst over Santa Cruz later that day.[6][7][8] During the next day, Xavier rapidly intensified into a category three severe tropical cyclone before passing over Tikopia early the next day. Xavier then reached its peak wind speeds of 175 km/h (110 mph) (10-min), 215 km/h (130 mph) (1-min) which made it a Category four cyclone early on October 24.[9] Xavier stayed at its peak wind speeds until early the next day when it started to rapidly weaken becoming a Depression early on October 26.[9][10] The remants of the depression were then tracked by RSMC Nadi until early on October 28 when they couldn’t be identified anymore.[6] There were no casualties reported as a result of Cyclone Xavier, with very little impact reported in the Solomon Islands and Vanuatu.[6][8]

Tropical Depression 02F

Tropical depression (Australian scale)
Clockwise vortex
Duration October 24 – October 29
Peak intensity Winds unknown  1004 mbar (hPa)

Late on October 24, RSMC Nadi reported that Tropical Depression 02F had formed embedded in an easterly trough about 555 km (345 mi), to the northwest of American Samoa.[8][9] Deep convection had persisted around the center however it was poorly organised with multiple low level circulation centers being reported with environmental shear around the system minimal.[9] During the next day as it moved towards the west and crossed the international dateline the depression lost all its deep convection.[10] The low level circulation center had become difficult to locate as the depression was being influenced unfavorably by the outflow from Cyclone Xavier.[8][10] As a result of the outflow the depression became separated from the southeasterly surge which had been helping to develop the system whilst the westerlies to the north of the system remained weak.[10][11] The final advisory was then issued on October 29 by RSMC Nadi as the depression had completely dissipated.[8]

Tropical Depression 03F

Tropical depression (Australian scale)
Clockwise vortex
Duration November 1 – November 3
Peak intensity Winds unknown  1004 mbar (hPa)

Early on November 1, RSMC Nadi reported that Tropical Disturbance 03F, had developed to the northeast of Fiji, with multiple circulation centers.[12] Later that day as the convection was now displaced to the north of the low level circulation center and the disturbance had become better organized it was designated as a tropical depression.[12] The system then meandered around in the same general area for a couple days without any development until the final advisory was issued by RSMC Nadi early on November 3.[12][13][14]

Severe Tropical Cyclone Yani

Category 3 severe tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
Duration November 16 – November 26
Peak intensity 140 km/h (85 mph) (10-min)  960 mbar (hPa)

Late on November 16 a weak tropical disturbance formed to the north-west of Tuvalu embedded within the South Pacific Convergence Zone.[6][15] The disturbance did not have any organised convection near the low level circulation centre and was located in an area of low vertical wind shear.[15] Early the next day whilst the organisation of the system had not improved much, there had been enough of an increase in convection in the northern and southern quadrants for RSMC Nadi to designate the disturbance as Tropical Depression 04F.[16] Over the next couple of days the depression gradually moved towards the south-west before the low level circulation center was relocated to the north of Vanuatu early on November 19.[17][18] The depression continued to gradually develop, with a Tropical Cyclone Formation Alert being issued late on November 21 as convection had erupted about the low level circulation centre with bands of convection wrapping around the low level circulation significantly.[6][19][20][21]

The depression was then upgraded to a category one tropical cyclone on the Australian Tropical Cyclone Intensity scale early on November 22, with the name Yani being assigned.[6][22] The JTWC also upgraded Yani to a tropical cyclone whilst the cyclone was located approximately 425 km, (265 miles), to the southeast of Honiara, in the Solomon Islands.[21] Yani then intensified fairly rapidly, being upgraded to a category two cyclone later that day while an eye was noted to be beginning to form.[23] Yani was then upgraded to a category three severe tropical cyclone early the next day as the developing eye had established itself well.[23] Later that day, Yani then reached its peak pressure of 960 hPa and its peak windspeeds of 140 km/h (85 mph) (10-min) and 130 km/h (80 mph) (1-min).[6][24] Yani maintained its peak intensity until early on November 24, when the storm began to weaken under the force of strengthening shear that tore away its low level circulation centre and was downgraded to a Tropical Depression by RSMC Nadi later that day.[6][25] The JTWC then issued their final advisory early the next day whilst RSMC Nadi kept issuing advisories until late on November 26 as the depression moved into TCWC Brisbane's area of responsibility. The JTWC later reported that it had dissipated that day.[24][26][27]

Tropical Depression 05F

Tropical depression (Australian scale)
Tropical storm (SSHWS)
Clockwise vortex
Duration November 29 – December 4
Peak intensity 55 km/h (35 mph) (10-min)  997 mbar (hPa)

An area of disturbed weather developed east-northeast of the Solomon Islands on November 28. RSMC Nadi began monitoring it as a tropical disturbance early on November 29 as it moved westward in a favorable environment for development. The disturbance later that day was classified as a tropical depression. On November 30, the Joint Typhoon Warning Center initiated advisories on the storm, internally numbered Tropical Cyclone 04P. Under heavy wind shear, the storm never developed further and the JTWC stopped advisories on December 1, shortly after RSMC Nadi.

Tropical Depression 06F

Tropical depression (Australian scale)
Clockwise vortex
Duration January 9 – January 17
Peak intensity 55 km/h (35 mph) (10-min)  1000 mbar (hPa)

On January 9 RSMC Nadi identified a tropical depression well east of the International Date Line, located in a sheared environment, with convection having persisted for 24 hours. It never developed further and late on January 15 RSMC Nadi noted that 06F had become extratropical. RSMC Nadi last noted it two days later.

Tropical Cyclone Zita

Category 2 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
Duration January 18 – January 25
Peak intensity 110 km/h (70 mph) (10-min)  975 mbar (hPa)

On January 16 a RSMC Nadi marine bulletin identified a tropical disturbance east of the International Date Line. The low level circulation center was unidentifiable but was estimated to be at the southwestern edge of the major convection. On January 18, RSMC Nadi identified the disturbance as a tropical depression while the system was still poorly organized. On January 20, the Joint Typhoon Warning Center noted the system and treated it as a tropical disturbance. On January 22, the JTWC issued a Tropical Cyclone Formation Alert on the system. The system was assigned the name Zita by RSMC Nadi and commented in their tropical disturbance summary that the cyclone had undergone explosive development. It then quickly began extratropical transition as it moved south-southeast, with the JTWC declaring it extratropical on January 24. It entered the warning area of TCWC Wellington later that day as it passed south of 25°S, and completed extratropical transition early on January 25.

Tropical Cyclone Arthur

Category 2 tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
Duration January 21 – January 27
Peak intensity 110 km/h (70 mph) (10-min)  975 mbar (hPa)
Main article: Cyclone Arthur (2007)

Forming as tropical depression on January 25, Arthur rapidly intensified into a strong Category 2 cyclone on the Australian intensity scale according to the Regional Specialized Meteorological Centre in Nadi, Fiji. The Joint Typhoon Warning Center assessed the storm to have peaked as a minimal Category 1 cyclone. Shortly after peaking in intensity, the cyclone began to deteriorate due to unfavorable conditions. Quickly moving towards the east-southeast, the Arthur began to undergo an extratropical transition. After turning towards the southeast, the center of circulation was almost fully exposed due to strong wind shear. However, Arthur briefly re-strengthened late on January 26 before becoming extratropical the next day. Tropical Cyclone Arthur affected several small islands during its existence. French Polynesia observed the most noteworthy effects from the storm, where several landslides damaged a few homes.

Tropical Depression 09F

Tropical depression (Australian scale)
Tropical storm (SSHWS)
Clockwise vortex
Duration February 1 – February 5
Peak intensity 55 km/h (35 mph) (10-min)  997 mbar (hPa)

RSMC Nadi noted a tropical disturbance in the general area of 10°S east of the International Date Line on January 30. On February 2, RSMC Nadi upgraded it to a tropical depression, and the next day, the Joint Typhoon Warning Center issued a Tropical Cyclone Formation Alert. On February 4, the JTWC upgraded the disturbance to a tropical cyclone, giving it the designation 11P. However, it quickly became extratropical, and the final warning was issued just 24 hours later. RSMC Nadi also stopped tracking the low on February 5.

Tropical Depression 12F

Tropical depression (Australian scale)
Clockwise vortex
Duration March 21 – March 25
Peak intensity 55 km/h (35 mph) (10-min)  998 mbar (hPa)

An area of disturbed weather formed northwest of Fiji on March 19 and moved southeast over the next three days with little change in organisation. On March 21, the system began to increase in organization, and RSMC Nadi designated the system Tropical Depression 12F late that day, noting that the potential for development into a tropical cyclone was low to moderate due to increasing wind shear to the south. The Joint Typhoon Warning Center issued a Tropical Cyclone Formation Alert on the now-quasi-stationary system the next day.[28] RSMC Nadi upgraded the potential for development to high and began issuing advisories later in the day, but the depression soon became disorganised due to increasing shear. The RSMC issued its last advisory early on March 25.[29]

Tropical Cyclone Becky

Category 2 tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
Duration March 25 – March 29
Peak intensity 110 km/h (70 mph) (10-min)  975 mbar (hPa)

An area of disturbed weather formed northwest of Vanuatu on March 24. The Tropical Cyclone Warning Centre in Brisbane began monitoring it as a tropical low early on March 25, before it moved eastward into the area of responsibility of RSMC Nadi later that day. RSMC Nadi designated the system Tropical Depression 13F and noted that it had a moderate potential for development into a tropical cyclone. Tropical disturbance advisories were initiated on March 26 as the system improved in organisation. The Joint Typhoon Warning Center designated it Tropical Cyclone 21P later that day. RSMC Nadi followed suit and upgraded the system to a tropical cyclone and named it Becky.

Becky initially strengthened quickly while moving south-southeastward, nearly reaching hurricane-equivalent intensity on March 27. RSMC Nadi initially issued a storm warning for Vanuatu, but the environment began to deteriorate, inhibiting any further strengthening. The cyclone began weakening late that day as it passed to the west of Vanuatu, and RSMC Nadi issued its final tropical disturbance advisory on Becky early on March 29.

Tropical Cyclone Cliff

Main article: Cyclone Cliff
Category 2 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
Duration April 1 – April 6
Peak intensity 100 km/h (65 mph) (10-min)  980 mbar (hPa)

Tropical Depression 14F, located around 15°S just west of the date line, was first warned on by RSMC Nadi on April 1 as a sheared system located in a highly sheared environment.[30] Despite this, the system managed to organise and intensify as it moved southeast, and was named Tropical Cyclone Cliff on April 4 near the international date line. The Joint Typhoon Warning Center designated it a tropical cyclone, the 23rd in the Southern Hemisphere for the season, later that day, as deep convective banding began to develop. Continuing to move generally southeast, Cliff peaked in intensity on April 5 before starting to weaken as it crossed into the area of responsibility of TCWC Wellington. Late that night, Cliff started to show signs of extratropical transition, causing Dvorak satellite intensity estimates to fall. The JTWC issued its final advisory the next day, followed later that day by TCWC Wellington as it completed transition.

Season effects

Name Dates active Peak classification Sustained
windspeeds		 Pressure Land areas affected Damage
(USD)		 Deaths Refs
Xavier October 21 – 29 Category 4 severe tropical cyclone 175 km/h (110 mph) 930 hPa (27.46 inHg) Solomon Islands, Vanuatu Minimal None
02F October 24 — 29 Tropical Depression Not Specified 1004 hPa (29.65 inHg) None None None
03F November 24 — 3 Tropical Depression Not Specified 1004 hPa (29.65 inHg) None None None
Yani November 16 – 26 Category 3 severe tropical cyclone 140 km/h (85 mph) 960 hPa (28.35 inHg) Solomon Islands
05F November 29 – December 4 Tropical depression 55 km/h (35 mph) 997 hPa (29.44 inHg)
06F January 9 – 17 Tropical depression 55 km/h (35 mph) 1000 hPa (29.53 inHg)
Zita January 18 – 25 Category 2 tropical cyclone 100 km/h (65 mph) 975 hPa (28.80 inHg) French Polynesia
Arthur January 21 – 27 Category 2 tropical cyclone 100 km/h (65 mph) 975 hPa (28.80 inHg) Samoan Islands, French Polynesia
09F February 1 – 5 Tropical depression Not Specified 997 hPa (29.44 inHg) Fiji
10F Not Specified Tropical disturbance Not Specified Not Specified
11F Not Specified Tropical disturbance Not Specified Not Specified
12F March 21 – 25 Tropical depression 55 km/h (35 mph) 998 hPa (29.47 inHg)
Becky March 25 – 29 Category 2 tropical cyclone 110 km/h (70 mph) 975 hPa (28.80 inHg) Solomon Islands, Vanuatu, New Caledonia
Cliff April 1 – 6 Category 2 tropical cyclone 100 km/h (65 mph) 980 hPa (28.94 inHg) Fiji
15F Not Specified Tropical depression Not Specified Not Specified
Season Aggregates
15 systems October 21 – April 6 175 km/h (110 mph) 930 hPa (27.76 inHg)

See also

Notes

    References

    1. ↑ 1.0 1.1 "Tropical Cyclone Operational Plan for the South Pacific and South-East Indian Ocean" (PDF). World Meteorological Organization. 2006. Archived (PDF) from the original on 11 September 2008. Retrieved 2008-08-15.
    2. ↑ 2.0 2.1 Climate Services Division (October 26, 2010). Tropical Cyclone Guidance for Season 2010/11 for the Fiji and the Southwest Pacific (Report). Fiji Meteorological Service. Archived from the original (PDF) on February 27, 2012. Retrieved April 6, 2012.
    3. ↑ "Tropical cyclone guidance for the 2006–07 season". Island Climate Update (National Institute of Water and Atmospheric Research) (73): 2. October 1, 2006. Retrieved January 9, 2012.
    4. ↑ "2006/2007 Cyclone Season". ENSO Update (PDF). Climate Services Division (Report) (1) (Fiji Meteorological Service). September 28, 2006: 2. Retrieved January 9, 2012.
    5. ↑ "Severe Weather Warnings issued on 20-10-2006". Fiji Meteorological Service, Bureau of Meteorology. MT Archive. 2006-10-20. Retrieved 2009-06-05.
    6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 "RSMC Nadi Season Summaries 2006, 2007, 2008" (PDF). Fiji Meteorological Service. World Meteorological Organization. 2008-12-08. Retrieved 2009-06-05.
    7. ↑ "Severe Weather Warnings issued on 21-10-06". Fiji Meteorological Service, Bureau of Meteorology. MT Archive. 2006-10-21. Retrieved 2009-06-06.
    8. ↑ 8.0 8.1 8.2 8.3 8.4 Gary Padgett (2007). "Gary Padgett's Monthly Tropical Cyclone Summary October 2006". Australian Severe Weather. Retrieved 2009-07-13.
    9. ↑ 9.0 9.1 9.2 9.3 "Severe Weather Warnings issued on 24-10-2006". Fiji Meteorological Service, Bureau of Meteorology. MT Archive. 2006-10-24. Retrieved 2009-06-29.
    10. ↑ 10.0 10.1 10.2 10.3 "Severe Weather Warnings issued on 25-10-2006". Fiji Meteorological Service, Bureau of Meteorology. MT Archive. 2006-10-25. Retrieved 2009-06-29.
    11. ↑ "Severe Weather Warnings issued on 26-10-2006". Fiji Meteorological Service, Bureau of Meteorology. MT Archive. 2006-10-26. Retrieved 2009-06-29.
    12. ↑ 12.0 12.1 12.2 "Severe Weather Warnings issued on 01-11-2006". Fiji Meteorological Service. MT Archive. 2006-11-01. Retrieved 2009-06-29.
    13. ↑ "Severe Weather Warnings issued on 02-11-2006". Fiji Meteorological Service. MT Archive. 2006-11-02. Retrieved 2009-06-29.
    14. ↑ "Severe Weather Warnings issued on 03-11-2006". Fiji Meteorological Service. MT Archive. 2006-11-03. Retrieved 2009-06-29.
    15. ↑ 15.0 15.1 "Tropical Cyclone Advisories issued on November 16". Fiji Meteorological Service. MT Archive. 2006-11-16. Retrieved 2009-07-14.
    16. ↑ "Tropical Cyclone Advisories issued on November 17". Fiji Meteorological Service. MT Archive. 2006-11-17. Retrieved 2009-07-14.
    17. ↑ "Tropical Cyclone Advisories issued on November 18". Fiji Meteorological Service. MT Archive. 2006-11-18. Retrieved 2009-07-14.
    18. ↑ "Tropical Cyclone Advisories issued on November 19". Fiji Meteorological Service. MT Archive. 2006-11-19. Retrieved 2009-07-14.
    19. ↑ "Tropical Cyclone Advisories issued on November 20". Fiji Meteorological Service. MT Archive. 2006-11-20. Retrieved 2009-07-14.
    20. ↑ "Tropical Cyclone Advisories issued on November 21". Fiji Meteorological Service. MT Archive. 2006-11-21. Retrieved 2009-07-14.
    21. ↑ 21.0 21.1 "Tropical Cyclone Yani: JTWC Advisories". Joint Typhoon Warning Center. Australian Severe Weather. 2006-11-21. Retrieved 2009-07-14.
    22. ↑ "Tropical Cyclone Advisories issued on November 22". Fiji Meteorological Service. MT Archive. 2006-11-22. Retrieved 2009-07-14.
    23. ↑ 23.0 23.1 "Tropical Cyclone Advisories issued on November 23". Fiji Meteorological Service. MT Archive. 2006-11-23. Retrieved 2009-07-14.
    24. ↑ 24.0 24.1 "Tropical Cyclone Yani: JTWC Best track". Joint Typhoon Warning Center. 2008-05-12. Retrieved 2009-07-14.
    25. ↑ "Tropical Cyclone Advisories issued on November 24". Fiji Meteorological Service. MT Archive. 2006-11-24. Retrieved 2009-07-14.
    26. ↑ "Tropical Cyclone Advisories issued on November 25". Fiji Meteorological Service. MT Archive. 2006-11-25. Retrieved 2009-07-14.
    27. ↑ "Tropical Cyclone Advisories issued on November 26". Fiji Meteorological Service. MT Archive. 2006-11-26. Retrieved 2009-07-14.
    28. ↑ WebCite query result
    29. ↑ WebCite query result
    30. ↑ WebCite query result

    External links