Cyclone Senyar formed unexpectedly overnight on 25–26 November and made landfall on Sumatra early the next morning.
It is Indonesia’s first recorded November cyclone and only the second ever documented in the region after Vamei in 2001.
IMD forecasts show the storm may retain cyclonic strength until 27 November before weakening.
Weather experts say no similar system has been recorded in the Malacca Strait for more than a century.
Meteorologists and weather enthusiasts have been caught off guard by Cyclone Senyar, a rare storm that formed overnight and made landfall on the Sumatra Island in Indonesia early on November 26, 2025 — the first November cyclone ever recorded in the country.
The cyclone formed on the intervening night of November 25 and November 26 and made landfall along the northeastern Indonesian coast of the island around 8.30 am Indian Standard Time with sustained wind speeds of 70-80 kilometre per hour (km/h) and gusts up to 90 km/h. It is only the second cyclone on record to strike the region, after Cyclone Vamei in 2001.
The India Meteorological Department (IMD) expects the cyclone to track west-southwest and maintain its strength until the morning of November 27. It forecast that the system may “recurve eastwards with gradual weakening during subsequent 24 hours”. A later update on November 26 suggested the storm could retain cyclonic intensity until the evening of November 27.
Earlier on November 25, the IMD said the depression that later intensified into Cyclone Senyar had formed that morning. While the agency predicted further intensification over the next 48 hours, it gave no indication that the storm would strengthen so rapidly or make such an early landfall.
Tropical cyclones in the North Indian Ocean rarely form in the Strait of Malacca or make landfall in Indonesia. Weather enthusiasts on the social media platform X (formerly Twitter) described Senyar as an exceptional event.
“We are now witnessing one of the rarest tropical cyclone events in recorded history. According to IBTrACS data [United States agency National Oceanic and Atmospheric Administration’s International Best Track Archive for Climate Stewardship project], no cyclonic-strength system has ever been documented in this exact region since 1842,” wrote Ajith Kumar from Chennai, who runs the Chennai Weatherman account on X.
“Historical records show there was never a cyclone formation in [the] Malacca Strait. There were in the past three depressions from Malacca which became cyclones. There is also the rare 2001 Vamei that passed through Malacca Strait as a cyclone,” the Tamil Nadu Weatherman account posted on X.
Kumar added: “Latest satellite data shows explosive convection near the Malacca Strait with massive rainfall over north Sumatra. It has intensified near land, and although land interaction may limit its lifespan, it still retains cyclone strength as of now. However, due to land interaction with Sumatra, the rugged terrain of Sumatra, easterly wind shear, and frictional effects, this is likely to be a very short-lived cyclone, quickly weakening after landfall.”
Even if short-lived, this cyclone remains one of the rarest ever recorded near the Malacca Strait, making this a historic meteorological event, he concluded.