Rainfall
Seasonal Rainfall Outlook: January-March 2018 (JFM)
Issued: 29 Dec 2017
Based on the NCEP CFSv2 model for JFM, much of the region is predicted to be in near average rainfall conditions (Figure 1), except for parts of the eastern Maritime Continent where above average rainfall is predicted (consistent with La Nina conditions that is expected to last until the first quarter of 2018), and western Borneo where below normal rainfall is predicted. Other models consulted (ECWMF, UK Met Office and JMA) show good agreement with this outlook, except for some parts of eastern Indonesia where two models (ECWMF and JMA) indicate below normal rainfall conditions.
The skill of the NCEP CFSv2 model over the north-eastern parts of Southeast Asia region is generally high for this time of year (Figures 2 and 3).
Figure 1: Rainfall anomaly for JFM 2018.
Figure 2: Anomaly Correlation Coefficient (ACC) of NCEP’s JFM (Jan-Feb-Mar) rainfall forecasts against APHRODITE.
Figure 3: Anomaly Correlation Coefficient (ACC) of NCEP’s JFM (Jan-Feb-Mar) rainfall forecasts against ERA-Interim.
The 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.