Rainfall
Seasonal Rainfall Outlook: June-August 2019 (JJA)
Issued: 30 May 2019
For JJA 2019, below-normal rainfall is favoured mainly over southern Southeast Asia. Some parts of northern Southeast Asia (southern parts of Myanmar, Thailand, Cambodia, and Vietnam are predicted to experience above-normal rainfall).
For JJA 2019, all three models – NCEP CFSv2, ECMWF and the UK Met Office (Figures 1-3) predict a higher likelihood of below-normal rainfall over southern Southeast Asia. The JJA outlook is different from the previous MJJ 2019 outlook, which favoured above-normal conditions especially around the equatorial region. The models’ skill for rainfall is relatively good over southern Southeast Asia.
There is no consistent prediction for most of northern Southeast Asia, although there is some increase in likelihood for above-normal rainfall for select regions (e.g. southern parts of Myanmar, Thailand, Cambodia, and Vietnam). Models’ skill scores are also low for the JJA season for this region.
Figure 1: Rainfall tercile summary predictions of NCEP model for JJA 2019.
Figure 2: Rainfall tercile summary predictions of ECMWF model for JJA 2019 (contains modified Copernicus C3S information).