Rainfall
Seasonal Rainfall Outlook: January-March 2023 (JFM)
Issued: 28 Dec 2022
For JFM 2023, above-normal rainfall is predicted over much of the northern Maritime Continent, Malay Peninsula, and southeastern Mainland Southeast Asia.
For JFM 2023, based on the multi-model ensemble (Figure 4), there is an increased chance of above-normal rainfall for much of the northern Maritime Continent and Malay Peninsula while below- to near-normal rainfall or no dominant tercile is predicted over southern Maritime Continent. There is a good agreement between all models for above mentioned regions (Figures 1 -3). The models’ skill is moderate to relatively high for northeastern parts of the Maritime Continent and low to moderate elsewhere.
For Mainland Southeast Asia, based on the multi-model ensemble (Figure 4), there is an increase in chance of above-normal rainfall for the southeastern region. Below-normal rainfall is also predicted over parts of northern Myanmar. However, model skill is low for this season for Mainland Southeast Asia.
For Mainland Southeast Asia, based on the multi-model ensemble (Figure 4), there is an increase in chance of above-normal rainfall for the southeastern region. Below-normal rainfall is also predicted over parts of northern Myanmar. However, model skill is low for this season for Mainland Southeast Asia.

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

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

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

Figure 6: Average climatological rainfall's upper tercile boundary for JFM 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.