Singapore was hammered by an exceptional thunderstorm in the wee hours of Wednesday, May 8, 2019 -- even as many Singaporeans slept through it.

It brought about a phenomenal lightning show, as it also wrecked some trees in Bedok.

It's not the work of Thor, the God of Thunder, of course.

Two consecutive Sumatra squalls

According to the Meteorological Service Singapore (MSS), the heavy downpour in the early morning was a result of two passing Sumatra squalls that were formed along the Strait of Malacca.

The first squall passed by Singapore between 2am and 5am, and the second one came by between 9am and 11am.

Here's a visualisation of the two squalls shared by Redditor PlastikSporc:

https://giphy.com/gifs/jUuQZsbmNYwqHqIfGT

What is a Sumatra Squall?

A Sumatra squall is an organised line of thunderstorms that approach Singapore from the Sumatra Island or the Strait of Malacca.

It is carried eastward by the southwesterly or westerly winds and typically forms overnight or in the early morning.

A squall brings gusty winds at speeds of up to 80km/h and heavy downpour that can last for one to two hours.

The weather forecast was accurate about having the squall this week, so brace yourself for more thundery showers.

Top photo from Haz's Twitter post