ONSET OF LA NIÑA
15 October 2021
DOST-PAGASA S & T Media Service
ONSET OF LA NIÑA 2021/ LA NIÑA ADVISORY # 1
Recent oceanic and atmospheric conditions indicate La Niña have developed in the tropical Pacific. Since July 2021, the sea surface temperatures in the central and equatorial Pacific started to cool and further strengthened in September reaching La Niña threshold. Based on the latest forecast, La Nina is likely to persist until the first quarter of 2022.
La Niña is usually associated with above normal rainfall conditions across most areas of the country during the last quarter of the year and early months of the following year.
Rainfall forecast from October 2021 to March 2022 suggests that most parts of the country will likely receive near to above normal rainfall conditions. In addition, four (4) to six (6) tropical cyclones (TCs), most of which are landfalling TCs, are expected to enter/develop in the Philippine Area of Responsibility (PAR). These TCs may further enhance the Northeast Monsoon and could trigger floods, flashfloods and rain-induced landslides over susceptible areas, particularly in the eastern sections of the country which normally receive greater amount of rainfall at this time of the year. Adverse impacts are likely over the vulnerable areas and sectors of the country.
PAGASA will continue to closely monitor the ongoing La Niña and regular updates/advisories shall be issued as appropriate. Meanwhile, all concerned government agencies and the public are advised to take precautionary measures to mitigate the potential impacts of this event.
VICENTE B. MALANO, Ph.D.