Hot mornings, rainy afternoons: Why Malaysia keeps getting thunderstorms despite the dry season

KUALA LUMPUR, Aug 3 — It may be the Southwest Monsoon, a period usually associated with hotter and drier weather, but many Malaysians have found themselves reaching for umbrellas on most afternoons in recent weeks.

The seemingly contradictory weather has prompted many to wonder whether this year’s monsoon is behaving unusually or whether climate change is making thunderstorms more intense.

According to Meteorological Department (MetMalaysia) director-general Mohd Hisham Mohd Anip, neither assumption tells the full story.

He said the recent run of afternoon thunderstorms was caused by temporary changes in wind patterns and the presence of higher levels of atmospheric moisture, rather than a shift in Malaysia’s seasonal weather.

“The afternoon thunderstorms that have occurred recently are due to changes in wind patterns and the presence of high moisture in our atmosphere,” he told Malay Mail.

“It is only temporary and weather conditions are expected to return to the normal, hotter and drier Southwest Monsoon pattern.”

The Southwest Monsoon, which began on May 14, is expected to continue until September. During this period, most parts of the country generally experience lower rainfall and more dry days compared with the wetter monsoon seasons.

MetMalaysia director-general Mohd Hisham Mohd Anip said the recent afternoon thunderstorms are temporary and were caused by shifting wind patterns and higher atmospheric moisture, rather than an unusual change in the Southwest Monsoon. — Bernama pic

However, Hisham said that does not mean thunderstorms disappear altogether.

“Hotter and drier weather during the Southwest Monsoon does not mean rain and thunderstorms will not occur,” he said.

“Changes in wind patterns and the presence of moist air can alter these conditions and produce more frequent rainfall, as we have experienced recently.”

Malaysia’s tropical climate also means thunderstorms can occur throughout the year, with activity typically becoming more frequent during the inter-monsoon periods in April and May, as well as October and November, when humid conditions and lighter winds favour thunderstorm development.

Hisham also addressed a common question raised whenever heavy afternoon storms disrupt traffic or outdoor plans — why weather warnings often arrive only shortly before the rain.

He explained that current forecasting technology has its limitations because thunderstorms form rapidly and over relatively small areas.

“Based on current technology, thunderstorm warnings cannot be issued too early because they develop within one to two hours and occur on a small scale of between one and 10 kilometres,” he said.

“For that reason, MetMalaysia continuously monitors weather developments and updates forecasts and warnings as soon as significant changes are detected.”

He urged the public to remain alert to changing weather conditions and obtain the latest forecasts through MetMalaysia’s official website, the myCuaca mobile application and the department’s social media platforms.

Rather than relying on the season alone, Hisham said Malaysians should expect weather conditions to change quickly and plan outdoor activities accordingly, particularly during periods of unstable atmospheric conditions.

MetMalaysia director-general Mohd Hisham Mohd Anip said thunderstorm warnings can often only be issued one to two hours in advance because the storms form rapidly and affect small areas. — Picture by Farhan Najib

Where did Malaysia see the most lightning and rain last year?

MetMalaysia’s latest climate summary also offers a snapshot of where some of the country’s most active weather has been recorded.

Subang, Selangor, experienced 294 days with lightning in 2025, the highest among the 42 principal meteorological stations monitored by the department.

Bayan Lepas, Penang, recorded 143 thunderstorm days, highlighting how frequently storms have developed along parts of the west coast.

East Malaysia also featured prominently in the department’s latest statistics.

Bintulu, Sarawak, recorded the country’s highest daily rainfall this year, receiving 516mm on January 1, while Kuching registered the highest annual rainfall at 4,974.2mm.

Sibu experienced the highest temperature recorded at 37.4 degrees Celsius on July 29, while Keningau, Sabah, recorded the lowest temperature at 17.5 degrees Celsius on September 25.

The strongest average daily winds were recorded in Bayan Lepas at 12.7 metres per second, while Kudat, Sabah, experienced the highest maximum wind speed at 23.3 metres per second.

Hisham also encouraged the public to stay updated through MetMalaysia’s website ([www.met.gov.my](http://www.met.gov.my)), the myCuaca mobile application and the department’s official social media channels, as thunderstorms often develop rapidly and weather warnings may only be issued shortly before conditions deteriorate.

For more information or weather-related queries, you can call the MET Hotline at 1-300-22-1638 or follow the department on all its social media platforms on X, Facebook, Instagram and YouTube.