Rainfall
Monthly Rainfall Outlook: May 2024
Issued: 30 Apr 2024
For May2024, above-normal rainfall is predicted for the equatorial region, with below-normal predicted for much of the rest of the ASEAN region.
For May 2024, above-normal rainfall is predicted for much of the equatorial region based on the multi-model ensemble (Figure 4). The ECMWF model (Figure 2) shows the highest confidence of above-normal rainfall, followed by the UK Met Office model (Figure 3), and the NCEP model (Figure 1). For above-normal rainfall over the equatorial region, models’ skill is moderate to good for the ECMWF and UK Met Office models, and low to moderate for the NCEP model.
Outside of the equatorial region, below-normal rainfall is predicted based on the multi-model ensemble (Figure 4). The NCEP model (Figure 1) has the highest confidence for below-normal rainfall over the northern ASEAN region, followed by the ECMWF model (Figure 2), while the UKMO model has the highest confidence of below-normal rainfall over southern parts of the southern ASEAN region (Figure 3). The models’ skill for below-normal rainfall is moderate to good for the northern ASEAN region and low to moderate for the southern ASEAN region.
Figure 1: Rainfall tercile summary predictions of NCEP model for May 2024 (contains modified Copernicus C3S information).
Figure 2: Rainfall tercile summary predictions of ECMWF model for May 2024 (contains modified Copernicus C3S information).
Figure 3: Rainfall tercile summary predictions of UK Met Office model for May 2024 (contains modified Copernicus C3S information).
Figure 4: Rainfall tercile summary predictions of the multi-model ensemble for May 2024 (contains modified Copernicus C3S information).
Figure 5: Average climatological rainfall's lower tercile boundary for May based on CHIRPS (Reference period: 1991-2020).
Figure 6: Average climatological rainfall's upper tercile boundary for May 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.