SINGAPORE — The prevailing dry weather conditions that Singapore has experienced in the past fortnight are expected to continue until the end of the month, the Meteorological Service Singapore (MSS) said. This is due to the prevailing south-west monsoon conditions, which are expected to persist for the rest of September.

In a weather update on Monday (Sept 16), the MSS added that rainfall for this month is “likely to be significantly below September’s climatological normal of 185.4mm”.

It is also likely to be the third consecutive month since July to have “more than 40 per cent below-normal monthly rainfall, giving rise to a potential rainfall-deficit situation”, the weather agency said.

A rainfall-deficit situation is defined as a period of at least three consecutive months with monthly rainfall more than 40 per cent below the climatological rainfall, averaged over the rainfall stations with long-term records across the island.

For the months of July and August, the total rainfall recorded at the rainfall stations across the island was 51 per cent and 82 per cent below normal respectively.

The last time this happened in Singapore was in 2014 from January to March, the MSS said, where the average rainfall total for each month across Singapore was 67 per cent, 89 per cent and 50 per cent below the month’s normal.

HAZE SITUATION COULD PERSIST

The MSS added that the prevailing dry weather conditions over southern South-east Asia are also expected to persist in the coming fortnight, with hotspots and smoke plumes observed over parts of Sumatra and Kalimantan in Indonesia.

“Singapore may continue to experience hazy conditions during the fortnight, depending on the wind conditions and the proximity and extent of the fires,” it said.

The National Environment Agency (NEA) said in a separate update that the prevailing winds are forecast to continue blowing from the south-east or south, resulting in Singapore continuing to experience “slightly hazy conditions”.

“For the next 24 hours, the 1-hr PM2.5 concentration readings are expected to be between Band I (Normal) and the low end of Band II (Elevated), and the 24-hr Pollutant Standards Index (PSI) is forecast to be in the high end of the Moderate range,” NEA said on Monday evening.

The 24-hour PSI, updated hourly on the NEA’s website, enters the “unhealthy” range if it crosses the 100-mark. A “moderate” reading is between a range of 51 and 100. Anything above 300 is considered “hazardous”.

SHOWERS IN LAST WEEK OF SEPTEMBER

The MSS said that in the last week of the month, localised short-duration showers can be expected in the afternoon on a few days due to the “strong solar daytime heating of land areas”.

“There could be some brief respite as the high pressure system over northern Australia is expected to weaken,” it added.

However, the prevailing warm conditions are forecast to continue for the rest of the month.

The daily temperature is expected to range between 26°C and 34°C on most days, with highs exceeding 35°C on a few days.

The nights are expected to be warm with daily minimum temperatures of 27°C or more on some days.

The MSS added that night-time temperatures in the southern and eastern coastal areas could be warmer, at around 28°C, when prevailing winds blowing from the south-east bring warm and humid air from the surrounding seas.