There is general consensus across international communities that the 2020–21 La Niña may have passed its peak and soon will return to neutral or normal conditions by the end of the wet season presumably around May or June. It is typical for La Niña to continue to influence our climate, even as the La Niña weakens. Generally speaking, La Niña tends to increase the likelihood of above-average rainfall across much of south-eastern coasts of PNG during the wet season months whilst the greater part of New Guinea Islands region tends to receive below average rainfall. It also increases the chance of tropical cyclone activities within our region as we saw this season.
The northwest monsoon or the wet season is now well established thanks to the late organization of the monsoon trough which is now located in the Coral sea and together with the prevailing La Niña condition, major parts of the country should be starting to receive much needed rainfall. This wet weather will continue for some time, at least until the end of the wet season. Furthermore, due to the late onset of the regular wet season, the country is expected to experience a much shorter wet season this year with increased likelihood of returning to more drier conditions come May or June.
The tropical cyclone season for PNG is from October to March each year. On average, PNG receives one tropical cyclone per season, however during La Niña episodes, the number of tropical cyclones forming in the waters of PNG increases. This season, we saw two tropical cyclones forming in the coral season which resulted in widespread heavy rainfall leading to floods in parts of Milne Bay, Central including NCD, Gulf and Oro provinces. Even though the threat has subsided, PNG National Weather Service will continue to monitor and report any developments associated with tropical cyclone activity within its areas of responsibility for the sake of our people.
(Refer to the pdf article below for full report)