Overview
- The Japan Meteorological Agency warns of heavy snowfall, including on plains, along the Sea‑of‑Japan sides of eastern and western Japan under a strong winter‑type pressure pattern.
- Through 6 a.m. JST on Jan. 4, forecast 24‑hour snowfall peaks are 40 cm in Kanto‑Koshin and Hokuriku, 30 cm in Kinki, 25 cm in Chugoku, and 5 cm in Shikoku.
- A frigid upper‑air mass near minus 36°C around 5,500 meters over Honshu is driving convective snow bands capable of producing intense bursts.
- On the Pacific side of eastern Japan, authorities urge caution for lightning and tornado‑like violent gusts associated with the system.
- In Nagasaki Prefecture, snow was observed on Jan. 2 with lows near or below freezing, and local forecasts through Saturday evening call for about 5 cm in mountains and 3 cm on plains with warnings for icy roads and snow accretion on power lines.