Climatology and Oceanography specialist Fredolin Tangang said this will see the west coast experiencing heavy rainfall until at least the end of the month.

MJO occurs due to interaction between the ocean and the atmosphere which causes large-scale convection activity, resulting in more moisture to fall, said Fredolin.

The Universiti Kebangsaan Malaysia professor added that MJO is in the midst of crossing Malaysia, moving from the Indian Ocean to the Pacific Ocean, which will see the country experiencing heavy rainfall.

Yesterday, Gurun, Yan and several other districts in Kedah experienced massive floods, with rivers bursting their banks. Bernama reported three victims were found dead in several locations around Gunung Jerai in Yan.

More than 2,500 residents in 500 homes have also been reported to be evacuated in Penang because of flash floods.

Typically, Fredolin said, July and August would be dry and hot due to the south-west monsoon but there is a disruption in weather because of the MJO phenomena.

By the time the dense moisture from MJO crosses Malaysia, he said, Malaysia would be entering the inter-monsoon rainy season.

“We may see heavy rainfall and thunderstorms in September and October, too,” he said.

He said the east coast monsoon will kick in in November, causing flash floods in the east coast.