Rainfall
Monthly Rainfall Outlook: January 2022
Issued: 30 Dec 2021
For January 2022, there is an increase in chance of above-normal rainfall over the eastern equatorial region and western Maritime Continent.
For January 2022, above-normal rainfall is predicted over the eastern equatorial region, western Maritime Continent, and parts of southeast Maritime Continent as seen in the multi-model ensemble (Figure 4). While the NCEP (Figure 1) and the UK Met Office models (Figure 3) predict a larger region and a higher likelihood of above-normal rainfall over the Maritime Continent, the ECMWF model (Figure 2) predicts the wet conditions mainly over the eastern equatorial region. The models’ skill is moderate to relatively good for the eastern Maritime Continent and Malay Peninsula, with low to moderate skill for western Maritime Continent and southeast Maritime Continent.
While all three models predict below-normal rainfall for the northern Philippines, the model skill for this region is generally low to moderate. Elsewhere, there is either no dominant tercile predicted or disagreement between the models. The models’ skill is generally low to moderate for Mainland Southeast Asia for this time of the year.
Figure 1: Rainfall tercile summary predictions of NCEP model for January 2022.
Figure 2: Rainfall tercile summary predictions of ECMWF model for January 2022 (contains modified Copernicus C3S information).
Figure 3: Rainfall tercile summary predictions of UK Met Office model for January 2022 (contains modified Copernicus C3S information).
Figure 4: Rainfall tercile summary predictions of the multi-model ensemble for January 2022 (contains modified Copernicus C3S information).
Figure 5: Average climatological rainfall's lower tercile boundary for January based on CHIRPS (Reference period: 1991-2020).
Figure 6: Average climatological rainfall's upper tercile boundary for January 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.