Medan, North Sumatra, Dec. 8 -- The Meteorology, Climatology, and Geophysics Agency (BMKG) has warned residents to remain alert for potential extreme weather across several areas of North Sumatra from December 8 to 15, 2025.

Head of BMKG Regional I, Hendro Nugroho, said on Monday that Tropical Cyclone Seed 918 in the Southwest Indian Ocean near Lampung is causing wind shifts and air mass convergence in North Sumatra.

He added that the cyclone seed is being supported by active atmospheric waves and the Madden-Julian Oscillation around its circulation center. The negative Indian Ocean Dipole (IOD) is expected to persist through December 2025.

Sea surface temperatures remain warm at 29-30 degrees Celsius, while high humidity is observed a...