After a span of heavy rainfall on Tuesday evening, hailstones have been reported in several areas of Singapore such as Yishun and Seletar. In addition to this, flash floods have been reported at Seletar North Link.
A Facebook user, who goes by the name of Mygolf Sg, posted an amazing video of hailstones during the rainfall at Seletar Country Club. A few other users also posted hail stone videos in other parts of Singapore, including Nanyang Polytechnic.
Experts say that hailstorms form within an unusually unstable air mass in which the temperature falloff with height is much greater than normal. During hailstorms, small ice particles that form above the freezing level generally collect either rainwater or cloud water on them, forming a water shell that freezes.
Hailstorms are quite common in mountainous regions, where the mountains force horizontal winds upwards that intensifies the updrafts within thunderstorms and forms hail.
However, hail is not uncommon in Singapore. During a heavy shower in 2014, hailstones were reportedly seen in Turf Club Road, while another hailstorm had uprooted trees and disrupted traffic in the country in 2013.
Meanwhile, a tree has fallen down on Tampines Expressway (TPE) due to the impact of the rain, according to Channel NewsAsia report.
On Twitter, the Land Transport Authority (LTA) posted at 5.10 pm that the Yio Chu Kang Road exit on the TPE was closed due to an "obstacle", which is believed to be the fallen tree.
At about 5.30 pm, PUB tweeted that both lanes of the Seletar Road were closed. The motorists were urged to avoid the area. However, 15 minutes later, the authorities tweeted again saying that the traffic was able to pass as the flood had subsided.
Several photos that have been circulated on social media showed fallen trees and branches in Ang Mo Kio and Yishun. One of those images also showed a fallen tree on a railing outside Yishun Secondary School.
In a recent weather forecast, the National Environment Agency (NEA) had said that Singapore will witness overcast and windy conditions with periods of moderate to heavy rainfall in coming weeks. The daily temperature is expected to range between 22º Centigrade and 28º C.