11/29/2023, 8:37 am EST

November 2023 Indian Ocean Dipole Outlook

Headline: +IOD Peak in December, Weakens by February Executive summary: One of the stronger +IOD episodes on record is peaking in December. However, steady weakening is forecast by Australia Bureau of Meteorology in January with weakening to neutral phase by February. The influence of +IOD on climate across the Indian Ocean and vicinity to Australia should fade after 2 months. Fig. 1-2: The west and east tropical Indian Ocean basin SSTA analysis. Synoptic discussion: A robust positive phase of the Indian Ocean Dipole (+IOD) is present as the western tropical Indian Ocean is much warmer than normal (Fig. 1) while the eastern tropics has significantly cooled (Fig. 2). According to the Australia Bureau of Meteorology (ABOM), +IOD episodes usually breakdown as the monsoon trough emerges in the southern hemisphere. However, due to the strength of +IOD, this anticipated process may be delayed. The latest IOD forecast from ABOM reveals +IOD peak occurs in December followed by a steady weakening early in 2024 to neutral phase by FEB-24 (Fig. 3). Fig. 3: The Australia Bureau of Meteorology Indian Ocean dipole forecast.