seasonal forecast for July, August, September 2018

Updated 5 July 2018

Summary of Outlook

The Southwest Monsoon season has been prevailing since early June 2018 and is expected to persist throughout the outlook period (Jul – Sep 2018). During this period, the prevailing winds are forecast to blow predominantly from the southeast or southwest over Southeast Asia. Between June and October, the southern ASEAN region typically experiences its traditional dry season.

For the upcoming July-August-September 2018 months, near-average temperatures are forecast for most parts of Southeast Asia, and relatively warmer conditions can be expected over Borneo, the Indonesian provinces of Sulawesi and Papua.

Around the equatorial region, rainfall is expected to be near-average to below-average. In some parts of the southern ASEAN region, occasional periods of drier weather can be expected which could this could lead to an increase in hotspot activities and the occurrence of smoke haze. Vigilance should be stepped up for any escalation of fire activities during this traditional dry season.

This outlook period is also the traditional rainy season of the northern ASEAN region. For the western coastal areas of Myanmar and the Philippines, the rainfall is forecast to be above-average. With the weather in the northern ASEAN region expected to be generally wet, hotspot activities in the region are likely to remain subdued. Over these region, the forecast skill of the models are low to moderate.

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.