Rainfall
Seasonal Rainfall Outlook: February-April 2022 (FMA)
Issued: 31 Jan 2022
For FMA 2021, above-normal rainfall is predicted for much of the ASEAN region north of the equator.
For FMA 2022, based on the multi-model ensemble (Figure 4), there is an increased chance of above-normal rainfall for much of the Maritime Continent, except for southern Sumatra, Java, southwestern Borneo, southern Sulawesi and Papua where no dominant tercile is predicted. The NCEP model (Figure 1) is most confident of above-normal rainfall over the Maritime Continent, compared to the ECMWF and UKMO models (Figures 2 and 3). Model skill is moderate to relatively high for northeastern and northwestern parts of the Maritime Continent and low to moderate elsewhere.
For Mainland Southeast Asia, all the models predict an increased chance of above-normal rainfall, apart from over northern Myanmar (all models) and parts of Lao PDR and Cambodia (ECMWF and UKMO models). Model skill is moderate for southern Mainland Southeast Asia and low to moderate elsewhere.
Figure 1: Rainfall tercile summary predictions of NCEP model for FMA 2022.
Figure 2: Rainfall tercile summary predictions of ECMWF model for FMA 2022 (contains modified Copernicus C3S information).
Figure 5: Average climatological rainfall's lower tercile boundary for FMA based on CHIRPS (Reference period: 1991-2020).
Figure 6: Average climatological rainfall's upper tercile boundary for FMA 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.