That is an elevated risk of cyclones for the 2018-19 Tropical Cyclone Season, which starts next month and will run until April.
In a statement, the New Zealand’s National Institute of Water and Atmospheric Research (NIWA) said the Southern Cook Islands may experience two to three named cyclones, which is higher than average for the islands. For the Northern Cook Islands, zero to one cyclones have been projected.
The forecasters have indicated that another seven to 11 named tropical cyclones (TC) could occur in the Southwest Pacific basin this coming cyclone season following the very early TC Liua that formed last month.
Cook Islands Meteorological Service director Arona Ngari said the outlook supported the trend of a high risk for cyclones during the upcoming season for the Cook Islands.
“The Cook Islands Meteorological Service will do its utmost to convey information on any incipient depression or cyclone at its early stage so as to get the communities prepared,” Ngari said.
NIWA said tropical cyclones were categorised in strength from one to five, with five being the most intense.
For the coming season, it said about four storms were anticipated to reach at least category three strength, with mean wind speeds of at least 118 kilometre per hour (km/h) winds.
“Past years with conditions similar to present suggest some of these storm systems may increase to at least category four strength, with mean wind speeds of 159 km/h,” NIWA added.
“Category five strength cyclones, where winds are greater than 196 km/h, have occurred during years with similar conditions ahead of the 2018/19 season (known as ‘analogue’ seasons). Therefore, all communities should remain alert and well-prepared for severe events.”
NIWA said tropical cyclone activity was expected to be slightly reduced for some countries during this season, especially for some islands west of the International Date Line, which does not include the Cook Islands.
It also said as with most years, activity was expected to increase during the second half of the season, from February to April, while the early season activity is expected to be near normal.
“Peak TC season is usually from January to March. In seasons with similar background climate conditions to the present, TC activity was elevated in a zone situated east of the International Dateline (which includes the Cook Islands) and in the western Gulf of Carpentaria,” NIWA said.
“In addition, the strongest TC anomalies were focused in the region between Samoa and the Cook Islands, which is associated with a northeast displacement of the South Pacific Convergence Zone (SPCZ) during El Niño events.
“On average, nearly half of the TCs that developed since the 1969-70 season have reached hurricane force with mean wind speeds of at least 64 knots (118 km/h).”
Meteorological Service’s Ngari is asking the public to start preparing for the upcoming cyclone season.
“Please are being encouraged to know their evacuation centres on their islands and refer to the cyclone information in our telephone directory pages 27-30 for more information,” he said.
“They can also use the Cyclone Tracking Map on page 213 in the same directory to monitor the path of a cyclone. Keep safe during this 2018-19 Tropical Cyclone Season.”
The last cyclone to affect the Cook Islands was Severe Tropical Cyclone Pat which passed directly over Aitutaki in 2010.