Review of Regional Weather Conditions for Second Fortnight of December 2019
1. Review of Regional Weather Conditions for Second Fortnight of December 2019
1.1 Northeast Monsoon conditions over the ASEAN region persisted into the second fortnight of December 2019. During the preview period, the prevailing winds blew from the northeast or east over the northern ASEAN region and from the northwest or northeast over most parts of equatorial ASEAN region.
1.2 Showers fell over many areas in the southern ASEAN region. East Malaysia, southern Sumatra, Kalimantan and Java recorded above-average rainfall while rainfall was below average in Peninsular Malaysia, and northern and central Sumatra. Parts of the Philippines received above-average rainfall due to the passage of Tropical Storm PHANFONE across central Philippines in late December 2019. Over the Mekong sub-region, dry weather persisted in the second fortnight of December 2019.
1.3 Despite the strong Madden–Julian Oscillation (MJO) signal in Phases 6 and 7 in the last week of December 2019, its contribution to the rainfall in the eastern Maritime Continent was not discernible and could have been masked by the presence of Tropical Storm PHANFONE.
1.4 The El-Niño Southern Oscillation (ENSO) remains neutral (i.e neither El Niño nor La Niña conditions). The Indian Ocean Dipole (IOD) is currently slightly positive but continues to weaken and a return to neutral state by early 2020 is likely.