Rainfall in the last 2 weeks exceeds the July average, Environment news and featured articles
Precipitation this month was slightly unusual, as the total precipitation recorded over the past two weeks exceeded the average monthly precipitation for July.
At the Changi health resort, the total precipitation recorded this month, as of 3 p.m. Tuesday, was 183.2 mm, more than the average monthly precipitation of 146.6 mm for July of previous years, said the ‘National Environment Agency (NEA) in a Facebook post on Tuesday.
In response to questions from the Straits Times, the NEA said the highest precipitation on Tuesday was 114.2mm in Bukit Panjang, and the highest on Monday was 100.2mm in Ulu Pandan.
During those two days, Singapore experienced prolonged and widespread showers, with the mercury dropping to 22.5 ° C in the Admiralty on Tuesday morning.
However, meteorologist and climatologist Koh Tieh Yong of the University of Social Sciences of Singapore noted that although the weather was colder and wetter than the long-term average during this period, it is still not considered as extreme.
“For comparison, the lowest daily minimum temperature for last month was 23.4 degrees Celsius, but the lowest record for June is 20.8 degrees Celsius in 1952 at the Changi climate station,” said Associate Professor Koh.
Dr Matthias Roth, professor of urban climatology in the geography department of the National University of Singapore, said the cooler temperature on Tuesday was due to afternoon thunderstorms and persistent cloud cover that was reducing the sunshine.
Weather experts said this week’s downpour was due to a combination of the ongoing southwest monsoon season, strong land warming and gusts from Sumatra.
Sumatran squalls refer to a line of thunderstorms that develop over the Indonesian island before sweeping east over Singapore. This results in heavy thunderstorms of short duration, usually before dawn, said Dr Roth.
Professor Koh said: “The intense convection occurs in the heart of a Sumatran gust. After that, the higher level clouds that make up the tail of a gust bring lighter but longer rain. . last a good part of the day. “
Convection occurs when warm, humid air rises above heavier cool, dry air, cooling the air and forming clouds. These clouds can then form rain and even thunderstorms.
Sumatran squalls occur throughout the year, but are more frequent during the inter-monsoon and southwest monsoon seasons, Professor Koh said.
Dr Dhrubajyoti Samanta, senior researcher at the Asian School of the Environment at Nanyang Technological University, noted that rainfall over Singapore between June and September is largely caused by the southwest monsoon.
The NEA said in its Facebook post that the rainy weather was due to the strong convergence of winds over Singapore and the surrounding area.
NEA said fine and warm weather is expected over the next few days as a dry air mass from the Java Sea persists over equatorial Southeast Asia during this period.
However, a climatic phenomenon known as the negative phase of the Indian Ocean Dipole is expected to occur in the coming months, which could bring more rainfall to the region, he added.