Early Action Rainfall (EAR) Watch
Current El Niño-Southern Oscillation (ENSO) status: The Australian Bureau of Meteorology's ENSO Outlook remains at La Niña, meaning that a La Niña has formed across the Pacific Basin and is expected to persist for the rest of the year. La Niña is normally associated with above average rainfall in the southern Cook Islands and below above average rainfall in the northern Cook Islands (opposite during El Niño).
Over the previous one to 12 months, Penrhyn's rainfall is at Drought Warning levels. In contrast, rainfall at Rarotonga has mainly been somewhat above normal for periods from one to 12 months.
For November, "High Chance Dry" alerts are in place for all northern Cook Island sites – Penrhyn, Rakahanga and Pukapuka. In contrast, "High Chance Wet" alerts are in place for the for all sites in the Southern Group: Rarotonga, Aitutaki, Mangia, Mauke and Manuae.
For November 2020 to January 2021, "High Chance Dry" alerts are in place for all northern Cook Island sites – Penrhyn, Rakahanga and Pukapuka. For the Southern Group, there are "High Chance Wet" alerts for Mauke and Manuae, and "Medium Chance Wet" alerts for Aitutaki, Mangia and Rarotonga. See table/maps below for additional information. It is very likely the northernmost Cook Islands will transition into meteorological drought in the coming months. See status table below for potential impacts.