Singapore to get drier and hotter

SINGAPORE - Singapore will be experiencing a drier and warmer than usual Southwest Monsoon season from June to early October this year, the Meteorological Service Singapore (MSS) said in its forecast.

This is partly due to the prevailing moderate El Niño conditions in the equatorial Pacific Ocean, which are likely to further develop in the months ahead.

With fewer rain days experienced this month, the total rainfall for June recorded at the Changi climate station so far is 38 per cent below the long-term average.

Lower rainfall is expected to persist over the next few months, the National Environment Agency (NEA) said. For July 2015, the total monthly rainfall is forecast to be 15-45 per cent below average.

To prepare for the drier months ahead, the Public Utilities Board has urged the community and businesses to conserve water.

Warmer days and nights have also been common recently. The average daily maximum and minimum temperatures for June so far are 31.9°C and 26.5°C, about 0.6°C and 1.7°C above the long-term average respectively .

Major global climate centres project a high likelihood that the tropical Pacific sea surface temperatures will continue to warm over the coming months and possibly reach strong El Niño levels.

During the the strongest El Niño on record in 1997, Singapore experienced a sharp 53 per cent reduction in June-September rainfall. During the moderate El Niño in 2009, Singapore's rainfall total was about 20 per cent below the long-term average. The average daily temperature for the same period in 2009 was 1.1°C higher than the long-term average of 27.4°C.

NEA said however, that the relationship between the strength of the El Niño and the impact on rainfall is not straightforward as there are other factors affecting local and regional rainfall patterns.

With drier and warmer weather expected over the southern ASEAN region in the coming months, there could be more fires, particularly in the fire prone provinces in Sumatra and Kalimantan. This would increase the risk of transboundary haze in the region.

The impact of the smoke haze on Singapore is dependent on factors such as the proximity and extent of the fires, the strength and direction of the prevailing winds, and the incidence and amount of rain, NEA said.

Recently, sporadic hotspot activities with localised smoke plumes have been seen in Sumatra. In addition, drier and warmer weather conditions have prevailed over Singapore and the surrounding region, indicating the start of the traditional dry season in the southern ASEAN region.

ljessica@sph.com.sg