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Cyclone Tam (2006)
Encyclopedia
Tropical Cyclone Tam was the first named storm of the 2005–06 South Pacific cyclone season. Forming out of a tropical depression on January 6, the storm gradually intensified, becoming a tropical cyclone on January 12 and receiving the name Tam. Although it was traveling at a quick pace, the storm gained organization and reached its peak intensity with winds of 85 km/h (50 mph) the following day. However, the increasing forward motion of the storm, combined with strengthening wind shear
, caused Tam to rapidly weaken on January 14. Around that time, it entered the Tropical Cyclone Warning Centre in Wellington, New Zealand
's area of responsibility. Shortly thereafter, the storm transitioned into an extratropical cyclone
and dissipated early the next day. Cyclone Tam produced heavy rainfall and strong winds over American Samoa
upon being named. The precipitation caused several mudslides and flooding, which inflicted $26,000 in damage. The storm also had minor effects on Niue
, Tonga, and Futuna
.
on January 6. The system, designated 04F by the Regional Specialized Meteorological Centre
(RSMC) in Nadi, Fiji tracked slowly towards the west. Although the depression was located within an area of low wind shear
, little intensification occurred, as a lack of low-level moisture hindered the development of deep convection
. By January 9, shower and thunderstorm activity associated with the disturbance increased as it began to interact with the South Pacific Convergence Zone
. Another tropical depression, 05F, also became increasingly organized and at one point was forecast to absorb 04F. Following the weakening of Tropical Depression 05F, 04F intensified. Around 2000 UTC
on January 11, the Joint Typhoon Warning Center
(JTWC) issued a Tropical Cyclone Formation Alert
as deep convection persisted around the center of circulation
for several hours.
The following day, the RSMC Nadi upgraded Tropical Depression 04F to a tropical cyclone and gave it the name Tam, making it the first named storm of the 2005–06 season. Several hours later, the storm passed close to Niuafo'ou
with winds of 65 km/h (40 mph). By 0000 UTC on January 13, the JTWC classified Tam as Tropical Cyclone 06P. Although the storm was tracking towards an area with stronger winds aloft, it was forecast to intensify. Due to the relatively fast movement of the storm, the increasing winds aloft had little effect on the storm, allowing it to intensify and attain winds of 85 km/h (50 mph) around 0600 UTC. However, with both wind shear and the forward motion of the storm continuing to increase, convection rapidly became dislocated from the center. Around 0000 UTC on January 14, Tam entered the area of responsibility of the Tropical Cyclone Warning Centre in Wellington, New Zealand
. With forward movement estimated at 75 km/h (45 mph) almost due south, the cyclone reached an unusually high latitude
as a tropical cyclone
. Coinciding with the time when Tam reached 33°S, it transitioned into an extratropical cyclone
. The remnants of the storm persisted for several hours before dissipating early on January 15.
. Only a few flights took off before officials closed the airport, stranding numerous passengers. Late on January 11, RSMC Nadi placed Tonga and Futuna under a tropical cyclone alert and also placed Tonga and Wallis under a strong wind warning. Early the next day RSMC Nadi placed northern Tonga under a tropical cyclone gale warning. Later that morning they canceled the tropical cyclone alert for Wallis and Futuna as Tam was not expected to directly affect Futuna anymore. During that afternoon RSMC Nadi placed Niue under a Tropical cyclone alert, as they predicted that Niue would be affected by Tam within 24 hours. Early on January 13 RSMC Nadi cancelled the tropical cyclone warnings and alerts for Tonga, whilst at the same time placing Niue under a tropical cyclone gale warning, however this gale warning was canceled later that day as Tam moved into the southern ocean.
On January 11, Tropical Depression 04F produced a record 293.2 mm (11.5 in) of rain in a 24 hour span on Rotuma
. However, little damage resulted from the heavy precipitation. Cyclone Tam produced heavy rainfall in American Samoa which triggered damaging floods. Several buildings were flooded, and an estimated 70% of the island's crops were destroyed. Sustained winds of up to 55 km/h (35 mph), with gusts reaching 95 km/h (59 mph), tore a few roofs off unsecured homes. Scattered power outages were reported throughout the island. A few landslides were also reported as a result of the storm. Damage from the storm totaled $26,000 on the island. Relatively little damage was recorded in Futuna; there, the storm downed several trees and stranded a yacht on a reef. On Niuafo'ou
, a weather station
recorded sustained winds of 55 km/h (35 mph) with gusts of up to 75 km/h (45 mph), along with a minimum pressure
of 991 hPa
(mbar
). Minor damage, consisting of fallen branches and isolated power outages also occurred on Niue.
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...
, caused Tam to rapidly weaken on January 14. Around that time, it entered the Tropical Cyclone Warning Centre in Wellington, New Zealand
Wellington
Wellington is the capital city and third most populous urban area of New Zealand, although it is likely to have surpassed Christchurch due to the exodus following the Canterbury Earthquake. It is at the southwestern tip of the North Island, between Cook Strait and the Rimutaka Range...
's area of responsibility. Shortly thereafter, the storm transitioned into an extratropical cyclone
Extratropical cyclone
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are a group of cyclones defined as synoptic scale low pressure weather systems that occur in the middle latitudes of the Earth having neither tropical nor polar characteristics, and are connected with fronts and...
and dissipated early the next day. Cyclone Tam produced heavy rainfall and strong winds over American Samoa
American Samoa
American Samoa is an unincorporated territory of the United States located in the South Pacific Ocean, southeast of the sovereign state of Samoa...
upon being named. The precipitation caused several mudslides and flooding, which inflicted $26,000 in damage. The storm also had minor effects on Niue
Niue
Niue , is an island country in the South Pacific Ocean. It is commonly known as the "Rock of Polynesia", and inhabitants of the island call it "the Rock" for short. Niue is northeast of New Zealand in a triangle between Tonga to the southwest, the Samoas to the northwest, and the Cook Islands to...
, Tonga, and Futuna
Futuna Island, Wallis and Futuna
Futuna is an island in the Pacific Ocean belonging to the French overseas collectivity of Wallis and Futuna. It is one of the Hoorn Islands or Îles Horne, nearby Alofi being the other...
.
Meteorological history
Tropical Cyclone Tam originated out of tropical depression while located about 370 km (230 mi) to the north-northeast of FijiFiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
on January 6. The system, designated 04F by the Regional Specialized Meteorological Centre
Regional Specialized Meteorological Centre
A Regional Specialized Meteorological Centre is responsible for the distribution of information, advisories, and warnings regarding the specific program they have a part of, agreed by consensus at the World Meteorological Organization as part of the World Weather Watch.-Tropical...
(RSMC) in Nadi, Fiji tracked slowly towards the west. Although the depression was located within an area of low 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...
, little intensification occurred, as a lack of low-level moisture hindered the development of deep 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...
. By January 9, shower and thunderstorm activity associated with the disturbance increased as it began to interact with the South Pacific Convergence Zone
South Pacific convergence zone
The South Pacific Convergence Zone , a reverse-oriented monsoon trough, is a band of low-level convergence, cloudiness and precipitation extending from the west Pacific warm pool south-eastwards towards French Polynesia...
. Another tropical depression, 05F, also became increasingly organized and at one point was forecast to absorb 04F. Following the weakening of Tropical Depression 05F, 04F intensified. Around 2000 UTC
Coordinated Universal Time
Coordinated Universal Time is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich Mean Time. Computer servers, online services and other entities that rely on having a universally accepted time use UTC for that purpose...
on January 11, the Joint Typhoon Warning Center
Joint Typhoon Warning Center
The Joint Typhoon Warning Center is a joint United States Navy – United States Air Force task force located at the Naval Maritime Forecast Center in Pearl Harbor, Hawaii...
(JTWC) issued a Tropical Cyclone Formation Alert
Tropical Cyclone Formation Alert
A Tropical Cyclone Formation Alert is a bulletin released by the U.S. Navy-operated Joint Typhoon Warning Center in Honolulu, Hawaii or the Naval Maritime Forecast Center in Norfolk, Virginia, warning of the possibility of a tropical cyclone forming from a tropical disturbance that has been...
as deep convection persisted around the center of circulation
Eye (cyclone)
The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The eye of a storm is a roughly circular area and typically 30–65 km in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the second most severe weather of a cyclone...
for several hours.
The following day, the RSMC Nadi upgraded Tropical Depression 04F to a tropical cyclone and gave it the name Tam, making it the first named storm of the 2005–06 season. Several hours later, the storm passed close to Niuafo'ou
Niuafo'ou
Niuafoou is the most northerly island in the kingdom of Tonga. It is a volcanic rim island of 15 km² and with a population of 650 in 2006.-Geography:...
with winds of 65 km/h (40 mph). By 0000 UTC on January 13, the JTWC classified Tam as Tropical Cyclone 06P. Although the storm was tracking towards an area with stronger winds aloft, it was forecast to intensify. Due to the relatively fast movement of the storm, the increasing winds aloft had little effect on the storm, allowing it to intensify and attain winds of 85 km/h (50 mph) around 0600 UTC. However, with both wind shear and the forward motion of the storm continuing to increase, convection rapidly became dislocated from the center. Around 0000 UTC on January 14, Tam entered the area of responsibility of the Tropical Cyclone Warning Centre in Wellington, New Zealand
Wellington
Wellington is the capital city and third most populous urban area of New Zealand, although it is likely to have surpassed Christchurch due to the exodus following the Canterbury Earthquake. It is at the southwestern tip of the North Island, between Cook Strait and the Rimutaka Range...
. With forward movement estimated at 75 km/h (45 mph) almost due south, the cyclone reached an unusually high latitude
Latitude
In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...
as a tropical cyclone
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...
. Coinciding with the time when Tam reached 33°S, it transitioned into an extratropical cyclone
Extratropical cyclone
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are a group of cyclones defined as synoptic scale low pressure weather systems that occur in the middle latitudes of the Earth having neither tropical nor polar characteristics, and are connected with fronts and...
. The remnants of the storm persisted for several hours before dissipating early on January 15.
Preparations and impact
As Tam was developing, residents attempted to evacuate the island by plane, with the primary target of FijiFiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
. Only a few flights took off before officials closed the airport, stranding numerous passengers. Late on January 11, RSMC Nadi placed Tonga and Futuna under a tropical cyclone alert and also placed Tonga and Wallis under a strong wind warning. Early the next day RSMC Nadi placed northern Tonga under a tropical cyclone gale warning. Later that morning they canceled the tropical cyclone alert for Wallis and Futuna as Tam was not expected to directly affect Futuna anymore. During that afternoon RSMC Nadi placed Niue under a Tropical cyclone alert, as they predicted that Niue would be affected by Tam within 24 hours. Early on January 13 RSMC Nadi cancelled the tropical cyclone warnings and alerts for Tonga, whilst at the same time placing Niue under a tropical cyclone gale warning, however this gale warning was canceled later that day as Tam moved into the southern ocean.
On January 11, Tropical Depression 04F produced a record 293.2 mm (11.5 in) of rain in a 24 hour span on Rotuma
Rotuma
Rotuma is a Fijian dependency, consisting of Rotuma Island and nearby islets. The island group is home to a small but unique indigenous ethnic group which constitutes a recognizable minority within the population of Fiji, known as "Rotumans"...
. However, little damage resulted from the heavy precipitation. Cyclone Tam produced heavy rainfall in American Samoa which triggered damaging floods. Several buildings were flooded, and an estimated 70% of the island's crops were destroyed. Sustained winds of up to 55 km/h (35 mph), with gusts reaching 95 km/h (59 mph), tore a few roofs off unsecured homes. Scattered power outages were reported throughout the island. A few landslides were also reported as a result of the storm. Damage from the storm totaled $26,000 on the island. Relatively little damage was recorded in Futuna; there, the storm downed several trees and stranded a yacht on a reef. On Niuafo'ou
Niuafo'ou
Niuafoou is the most northerly island in the kingdom of Tonga. It is a volcanic rim island of 15 km² and with a population of 650 in 2006.-Geography:...
, a weather station
Weather station
A weather station is a facility, either on land or sea, with instruments and equipment for observing atmospheric conditions to provide information for weather forecasts and to study the weather and climate. The measurements taken include temperature, barometric pressure, humidity, wind speed, wind...
recorded sustained winds of 55 km/h (35 mph) with gusts of up to 75 km/h (45 mph), along with a minimum pressure
Atmospheric pressure
Atmospheric pressure is the force per unit area exerted into a surface by the weight of air above that surface in the atmosphere of Earth . In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point...
of 991 hPa
Pascal (unit)
The pascal is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force per unit area, defined as one newton per square metre...
(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...
). Minor damage, consisting of fallen branches and isolated power outages also occurred on Niue.
See also
- 2005–06 South Pacific cyclone season
- Cyclone Urmil (2006)Cyclone Urmil (2006)Tropical Cyclone Urmil was a short lived storm that explosively intensified to reach its peak intensity as a high-end Category 2 cyclone on the Australian Scale, just 12 hours after being named. Forming out of a tropical disturbance early on January 14, Urmil quickly intensified before...