The signs of an impending thunderstorm could only be known about three hours before the incident and it was not determined several days earlier as disseminated in social media, said Meteorological Department director-general Che Gayah Ismail.

She said using the latest technology, the gathering of clouds that might trigger a thunderstorm could only be detected three hours earlier.

“Any initial signs (of a thunderstorm) will be announced on the department’s official website and via our official social media,” she said at a news conference in Putrajaya yesterday.

The news conference was held following the dissemination of rumours via Whatsapp that the Meteorological Department had issued warnings of a tornado in Kuala Lumpur and Putrajaya, and Che Gayah also confirmed that not all thunderstorms would result in a tornado.

The information alleged that thunderstorms with strong winds at 80 to 100kph would hit Kuala Lumpur and Putrajaya from Oct 27 to 30 and they could cause a tornado in the areas.

“Each thunderstorm is usually followed by strong winds with a minimum speed of 50kph even though it is not the same with a tornado,” she said, adding that the rumours might have been spawned by recordings of several waterspouts on smartphones.

According to records, she said the country had experienced several strong wind incidents caused by thunderstorms with the highest recorded in Kuching, Sarawak in 1992 when the wind speed reached 150kph.  

Currently, the Meteorological Department has 180 automatic weather stations throughout the country capable of detecting thunderstorms and is now in the process of completing another 60 more such stations.  

Che Gayah said the occurrence of thunderstorms, especially on the west coast of peninsular Malaysia now was normal during a transitional monsoon.  

“Thunderstorms starting from mid-day to the night at the moment are expected to persist until the first or second week of November,” she said.

Che Gayah said it would be followed by the North-East Monsoon with the monsoon season starting in the second week of November to early March next year.

“So during the monsoon season, we will experience four to six episodes of heavy rain starting from Kelantan, to Terengganu, east Pahang and east Johor and to Sabah and Sarawak,” she said.

She advised the people to obtain official information on weather warnings issued by the Meteorological Department via its website at http://www.met.gov.my , Facebook page at http://www. facebook.com/malaysiamet , Twitter at http://twitter.com/malaysiamet or its 24-hour hotline at 1-300-22-1638.

- Bernama