Rainfall
Seasonal Rainfall Outlook: October-December 2020 (OND)
Issued: 28 Sep 2020
For OND 2020, above-normal rainfall is predicted for much of the Maritime Continent and the coastal regions of Viet Nam.
For OND 2020, all three models – NCEP, ECMWF, and UK Met Office (Figures 1-3) – predict an increased chance of above-normal rainfall over the Maritime Continent (apart from northern Sumatra, Peninsular Malaysia and northwestern Borneo where below- to near-normal rainfall is predicted) and the coastal regions of Viet Nam. The model skill is moderate to high in these regions with above-normal rainfall, but low for the three regions of the Maritime Continent where below- to near-normal rainfall is predicted.
Elsewhere, the models show inconsistent forecasts or have low skill.
Elsewhere, the models show inconsistent forecasts or have low skill.
Figure 1: Rainfall tercile summary predictions of NCEP model for OND 2020.
Figure 2: Rainfall tercile summary predictions of ECMWF model for OND 2020 (contains modified Copernicus C3S information).
Figure 5: Average climatological rainfall's lower tercile boundary for OND based on CHIRPS (Reference period: 1981-2010).
Figure 6: Average climatological rainfall's upper tercile boundary for OND based on CHIRPS (Reference period: 1981-2010).
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.