ASMC issued Level 3 Warning on the haze situation in Sumatra on 2 Sep 2015. Following is the statement from ASMC:
Upgrade of Alert Level 2 to Alert Level 3 for Sumatra
In the past week, the prevailing dry weather has led to a further escalation of hotspot activities over Sumatra. Increasing hotspot clusters and widespread moderate to dense smoke haze have been detected in southern and central Sumatra. Based on surveillance by the NOAA-18 satellite, 222 and 380 hotspots were detected in Sumatra on 31 August and 1 September respectively. In recent days, the smoke haze from Sumatra has spread to some parts of the region including western Peninsular Malaysia and affected the air quality there.
In the coming days, the current dry weather conditions over southern and central Sumatra are expected to persist. Under the prevailing southeasterly to southerly wind conditions, transboundary smoke haze could continue to spread to some parts of the region.
ASMC Alert Levels
ASMC regularly issues advisories for transboundary smoke haze to the respective ASEAN stakeholders. The criteria for the issuance of advisory is in accordance with the operation procedure adopted at the Palembang Workshop on the Operationalisation of the Procedures of the Panel of ASEAN Experts on Fire and Haze assessment and Coordination. The different levels of trigger points can be classified as the following:
Exceeding 150 hotspots in 2 consecutive days with dense smoke plumes; dry weather persisting; and prevailing winds blowing towards ASEAN countries.
Exceeding 250 hotspots in 2 consecutive days with dense smoke plumes; dry weather persisting; and prevailing winds blowing towards ASEAN countries.