Cyclone Rona
Encyclopedia
Severe Tropical Cyclone Rona-Frank (JTWC
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...

 designations 20P and 22P; RSMC Nadi designation 16F) was a damaging tropical cyclone that made landfall on Queensland, Australia on February 11, 1999, before dissipating and reforming to hit New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

 nine days later.

Forming during the second week of February, Rona rapidly intensified just before making landfall, causing $150 million (1999 USD; $ 2011 USD) in damage in Queensland. After crossing the Cape York Peninsula
Cape York Peninsula
Cape York Peninsula is a large remote peninsula located in Far North Queensland at the tip of the state of Queensland, Australia, the largest unspoilt wilderness in northern Australia and one of the last remaining wilderness areas on Earth...

, the upper-level circulation was eventually tracked moving back onto the Coral Sea
Coral Sea
The Coral Sea is a marginal sea off the northeast coast of Australia. It is bounded in the west by the east coast of Queensland, thereby including the Great Barrier Reef, in the east by Vanuatu and by New Caledonia, and in the north approximately by the southern extremity of the Solomon Islands...

 and reforming into another tropical cyclone, now named Frank. Frank rapidly intensified before making landfall on New Caledonia in the early morning of February 20. Despite being stronger at landfall in New Caledonia, Frank caused only minor damage there.

Due to the severity of damage in Queensland, the name "Rona" was retired and replaced with "Ruby" on the Australian region's list of tropical cyclone names.

Meteorological history

During the second week of February 1999, a tropical low formed in the Coral Sea
Coral Sea
The Coral Sea is a marginal sea off the northeast coast of Australia. It is bounded in the west by the east coast of Queensland, thereby including the Great Barrier Reef, in the east by Vanuatu and by New Caledonia, and in the north approximately by the southern extremity of the Solomon Islands...

 while embedded in a monsoon trough
Monsoon trough
The monsoon trough is that portion of the Intertropical Convergence Zone which extends into or through a monsoon circulation, as depicted by a line on a weather map showing the locations of minimum sea level pressure, and as such, is a convergence zone between the wind patterns of the southern and...

. A middle- to upper-level trough over eastern Australia caused the tropical low to move slowly to the east. However, it began to weaken late on February 9 and had dissipated within 24 hours– causing the tropical low to slow down and become nearly stationary. The dissipation of the trough caused the upper levels of the tropical low to become favorable for development and as a result, the system rapidly intensified on February 10.

Early on February 10, 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...

 (TCFA) as the deep convection had increased in organization. In addition, it was noted that the upper-level outflow had improved as the system moved east-southeast at 7 km/h (4 mph). Late that same day, the Tropical Cyclone Warning Center (TCWC) at Brisbane, Australia upgraded the tropical low into a category one tropical cyclone, naming it "Rona". At the time of the upgrade, the storm was 310 km (192.6 mi) east of the North Queensland coast. Simultaneously, the JTWC upgraded Rona into a tropical storm, giving it the designation "20P".

Early on February 11, TCWC Brisbane upgraded Rona to a category two tropical cyclone. Soon afterwards, a mid-level ridge south of the storm strengthened, causing Rona to rapidly accelerate to the west-northwest. At 1200 UTC, Rona reached its peak intensity as a category three severe tropical cyclone with winds of 130 km/h (80 mph). Around this time, the maximum wind gust of 159 kilometres per hour (99 mph) was recorded, at Low Isles. Severe Tropical Cyclone Rona made landfall near the mouth of the Daintree River
Daintree River
The Daintree River runs through the Daintree Rainforest in the Cape Tribulation region of Queensland in northern Australia. It is located about 100 kilometres northwest of Cairns in far north tropical Queensland and drains an area of 2,125 square kilometres. The river, along with the Daintree...

 at around 1300 UTC while still at peak intensity. Operationally, the JTWC assessed Rona to have made landfall with winds of 120 km/h (75 mph). However, in their post-season analysis, this was lowered to 105 km/h (65 mph). Five hours later, TCWC Brisbane downgraded Rona into a tropical low. In addition, the JTWC issued their final advisory late on February 12 as Rona was predicted to move into the Gulf of Carpentaria
Gulf of Carpentaria
The Gulf of Carpentaria is a large, shallow sea enclosed on three sides by northern Australia and bounded on the north by the Arafura Sea...

 and dissipate. After February 12, the low-level circulation center of Rona became difficult to definitely identify, due to the formation of several smaller circulation centers. Despite this, the circulation at 850 hPa
HPA
-Organizations:*Halifax Port Authority, a port authority in Canada*Hamburg Port Authority, the port authority for the Port of Hamburg, Germany*Health Protection Agency, a health organization in the United Kingdom...

 was still tracked as it curved back to the east to the Coral Sea
Coral Sea
The Coral Sea is a marginal sea off the northeast coast of Australia. It is bounded in the west by the east coast of Queensland, thereby including the Great Barrier Reef, in the east by Vanuatu and by New Caledonia, and in the north approximately by the southern extremity of the Solomon Islands...

.

Late on February 16, the JTWC issued a TCFA for the system which was about 555 km (344.9 mi) east-northeast of Rockhampton
Rockhampton
Rockhampton can refer to:* Rockhampton, Queensland is a city in Queensland, Australia* Rockhampton City, Queensland, a suburb of Rockhampton, Queensland* Electoral district of Rockhampton, Queensland, Australia...

. At the time, satellite imagery showed a well-defined lower-level circulation center with deep convection. Two hours later, the JTWC issued their first warning on the system, designating it "22P". During the evening of February 17, the Regional Specialized Meteorological Center
Regional Specialized Meteorological Center
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) at Nadi, Fiji began monitoring the system as a tropical depression with the designation "16F".

During the afternoon of February 18, the JTWC upgraded Tropical Depression 22P into a tropical storm. Late that night, RSMC Nadi reported that Tropical Depression 16F had moved east of 160°E and intensified into a category one tropical cyclone, and named it "Frank. At the time of the upgrade, the storm was centered 690 km (428.7 mi) west-northwest of Nouméa, New Caledonia. By this time, an upper-level trough over eastern Australia moved into the Tasman Sea
Tasman Sea
The Tasman Sea is the large body of water between Australia and New Zealand, approximately across. It extends 2,800 km from north to south. It is a south-western segment of the South Pacific Ocean. The sea was named after the Dutch explorer Abel Janszoon Tasman, the first recorded European...

, improving the poleward outflow. This caused Frank to rapidly intensify over the next 24 hours. Frank was assessed to have made landfall near the northern tip of New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

 at peak intensity with winds of 145 km/h (90 mph) at 0000 UTC on February 20. Operationally, the JTWC had assessed the peak intensity at 185 km/h (115 mph), however this was lowered to 175 km/h (110 mph) in post-season analysis.

After making landfall on New Caledonia, Frank maintained peak intensity for 18 hours. Soon afterwards, Frank entered an area of northwesterly wind shear and cooler sea surface temperatures, causing Frank to weaken rapidly. During the morning of February 21, RSMC Nadi passed warning responsibility to TCWC Wellington
Meteorological Service of New Zealand Limited
Meteorological Service of New Zealand Limited was established as a State-Owned Enterprise in 1992. It employs about 215 staff and its headquarters are in Wellington, New Zealand...

 as the cyclone had moved south of 25°S. 18 hours later, Frank merged with a trough to form an intense 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...

. This extratropical cyclone eventually made landfall on the South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...

 of New Zealand near Westport
Westport, New Zealand
-Economy:Economic activity is based around fishing, coal mining and dairy farming. Historically, gold mining was a major industry, and coal mining was much more extensive than today . However, the region still is home to New Zealand's largest opencast mining operation in Stockton...

 with monitoring of the system ceasing on February 27.

Impact and Retirement

During its Queensland landfall, Cyclone Rona caused a 1 metres (3.3 ft) storm surge in Port Douglas. Also, at the mouth of the Mossman River, a 1.4 metres (4.6 ft) storm surge was noted. The highest rains associated with Rona, 1870 millimetres (73.6 in), were measured at Bellenden Ker in Northern Queensland. On February 12, a state of disaster was declared for Cairns and Innisfail due to the severity of damage caused by the storm.

Strong winds and flooding caused significant crop and infrastructure damage from Cape Kimberly to Cape Tribulation. In the Cow Bay area, two houses were destroyed, twelve others were damaged, and a car was crushed by a falling tree. Seven deaths were attributed to the storm in Queensland. Eventually, the damage estimates from Cyclone Rona totaled $150 million (1999 USD; $ 2011 USD) in Queensland.

Despite passing only 27 km (16.8 mi) west of Nouméa, the overall damage in New Caledonia was minimal. Some of the townships in the northern and western sides of the island experienced power outages and disruptions to the water supply and communication with landslides on some coastal roads. In addition crop damage was found in the northeastern side of the island. Despite this, there were no reports of severe damage to infrastructure or any casualties. Offshore, three men were found 545 km (338.6 mi) southwest of Nouméa after their yacht sank three days previously on February 21.

Due to the damage from Cyclone Rona, the name "Rona" was retired and was replaced with "Ruby". However, due to the minimal damage in New Caledonia, the name "Frank" was not retired and remains on the South Pacific naming lists.
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