Jakarta. Cyclone Senyar, an unusual weather phenomenon for the Malacca Strait, has unleashed a series of deadly disasters across Sumatra, as Indonesia’s meteorological agency warns that shifting climate patterns are making rare tropical systems more likely to form near the archipelago.

The Meteorology, Climatology and Geophysics Agency (BMKG) said the Malacca Strait is typically shielded from cyclones due to its proximity to the equator, but global climate shifts and changing regional atmospheric dynamics have increased the likelihood of low-pressure systems and cyclone seeds forming closer to Indonesia in recent years.

Andri Ramdhani, BMKG’s Director of Public Meteorology, said several cyclonic systems have approached Indonesia over the past five years despite the country not being on a typical cyclone track. “A tropical system like Senyar rarely develops in the Malacca Strait, especially one strong enough to affect land. This is why public preparedness is crucial,” he said on Thursday.

BMKG said Senyar has triggered days of extreme weather, including heavy rain, strong winds, and coastal flooding, raising risks of landslides, flash floods, and transport disruptions on land and at sea. The cyclone originated as tropical disturbance 95B on Nov. 21 in waters east of Aceh and has since battered Aceh, North Sumatra, and West Sumatra.

In North Sumatra’s Tapanuli region, landslides and flash floods have caused some of the worst devastation in years. In the coastal city of Sibolga, at least 47 people were reported buried by landslides. Police data on Thursday show 24 people have been confirmed dead across the province following floods and landslides that hit multiple districts.

In South Tapanuli’s Batangtoru subdistrict, hundreds of homes were swept away after a surge of mud, logs, and water barreled through residential areas on Tuesday morning. Many residents were unable to flee in time, and search operations continue as rescuers, many of them locals using rudimentary tools, struggle with unstable terrain and poor visibility.

Aceh has also been heavily impacted, with 12 districts and cities inundated by major flooding between Wednesday and early Thursday. Ten local governments have declared a state of emergency, with nearly 1,500 people displaced and two fatalities reported, according to the provincial disaster agency BPBA.

In West Sumatra, flooding cut off the main route connecting Padang and Bukittinggi after the Batang Anai River overflowed in Padang Pariaman. Floodwaters rose to about 50 centimeters, forcing vehicles to halt on Thursday. “We’ve been stuck since 7 a.m.,” said Doni, a truck driver transporting subsidized cooking gas cylinders. Several motorcyclists who attempted to cross stalled mid-water and had to push their vehicles to safety as the heavy rain continued.