Arctic Air Plunges Across US Ending Warmth; Extreme Weather Hits Japan, South America, and New Zealand
Arctic air has surged south across the United States, bringing an end to a week of record warmth in the southern and midwestern regions. Earlier, a low-pressure system on the West Coast had drawn warm, humid air from the Gulf of Mexico, causing spring-like conditions with temperatures 15 to 20 degrees Celsius above normal for late December. However, this week a ridge has formed across the western US, allowing a polar air mass to move southward, resulting in freezing temperatures and an increased risk of snow.
In South America, São Paulo recorded 36.2°C, marking the highest December temperature on record. This intense heat is expected to expand into parts of Chile and Argentina in the coming days.
Meanwhile, Japan is experiencing winter conditions characterized by heavy snow and icy roads. A fatal pile-up occurred in Minakami, Gunma, resulting in two deaths and dozens of injuries. Additional snowfall is forecast as Siberian winds combine with sea-effect snow from the Sea of Japan.
In New Zealand, the South Island faced heavy rain, hail, and lightning, with the Canterbury Plains struck by a rare and powerful supercell thunderstorm. The North Island is forecast to endure strong winds and 100 to 200 millimeters of rainfall as a low-pressure system moves through the area.
