Rainfall
Seasonal Rainfall Outlook: December 2023 - February 2024 (DJF)
For DJF 2023-2024, models predict an increased chance of below-normal rainfall over the southern Maritime Continent and parts of the Philippines, and above-normal rainfall over parts of the equatorial region.
For DJF 2023-2024, below-normal rainfall is predicted over the southern Maritime Continent and parts of the Philippines, and above-normal rainfall predicted over parts of the equatorial region, based on the multi-model ensemble (Figure 4). The NCEP model (Figure 1) shows the highest confidence for above-normal rainfall, followed by the UK Met Office model (Figure 3) and then the ECMWF model (Figure 2). Models’ skill is moderate to good for below-normal rainfall, and low to moderate for above-normal rainfall for the mentioned region.
For Mainland Southeast Asia, all three models (Figures 1 – 3) agree on above-normal rainfall over the northeastern region. However, it is the dry season for the region and the models’ skill is low to moderate. Elsewhere, there is disagreements between the models and the models' skill is low for this season.

Figure 1: Rainfall tercile summary predictions of NCEP model for DJF 2023-2024 (contains modified Copernicus C3S information).

Figure 2: Rainfall tercile summary predictions of ECMWF model for DJF 2023-2024 (contains modified Copernicus C3S information).

Figure 5: Average climatological rainfall's lower tercile boundary for DFJ based on CHIRPS (Reference period: 1991-2020).

Figure 6: Average climatological rainfall's upper tercile boundary for DJF based on CHIRPS (Reference period: 1991-2020).
The qualitative outlook is assessed for the region in general. For specific updates on the national scale, the relevant ASEAN National Meteorological and Hydrological Services should be consulted.