Highlights

• In the first-half of 2020,
  • The Indian Ocean Dipole (IOD) returned to the neutral phase after a strong, positive episode in the second half of 2019. 
  • El Niño Southern Oscillation (ENSO) was also in a neutral state as predicted. Thus, neither a significant ENSO nor IOD event was present to influence the northern ASEAN region’s fire hotspot count, which was similar to that of 2019. 
  • In the absence of a significant ENSO or IOD event, the influence of climate change on sea-surface temperatures was more visible, while other sources of shorter-term variability drove weather patterns in the region. For example, the heavy rainfall events in East Java (Indonesia), central Myanmar, and northern Viet Nam. 
  • On the other hand, Thailand experienced a prolonged dry period which extended into early 2020 despite a weakening IOD, and southern Philippines experienced drought which could be attributed partly to a less active tropical cyclone season.
• For the period September 2020 to February 2021,
  • Models predict a high likelihood of neutral IOD conditions but favoured the development of La Niña conditions by the last quarter of 2020.
  • In line with the possibility of a La Niña development, wetter conditions are predicted by models over parts of Southeast Asia, particularly over the equatorial region.