The National Center for Hydro-Meteorological Forecasting has announced that from October 4, northern Vietnam will be affected by a cold air mass, leading to rain, moderate thunderstorms, and in some areas, heavy to very heavy rainfall. The temperature in the northern region is expected to drop, with nighttime temperatures ranging from 19 to 22 degrees Celsius, and in mountainous areas, it could be as low as 14 to 17 degrees Celsius.

As the cold air mass moves southward, it is predicted to impact the northeastern region and later affect other parts of northern Vietnam and areas from Thanh Hoa to Hue. Winds will shift to the northeast at levels 2-3 inland and 3-4 along the coast.

From the evening of October 4 to the morning of October 5, Hanoi will experience rain and thunderstorms, with some areas likely to see heavy rainfall. The cold air will also bring about a significant temperature drop, marking a shift from the recent warm weather.

During this transitional season, the clash between warm and cold air masses may lead to severe weather phenomena, including thunderstorms, hail, and strong winds. The meteorological agency has issued warnings about the potential impacts on agriculture, infrastructure, and transportation due to heavy rainfall and strong winds.

Additionally, the cold air will affect marine weather conditions. From the early morning of October 5, strong northeast winds are expected in the Gulf of Tonkin, reaching levels 6-7, with gusts up to 8-9 and wave heights of 2-4 meters, creating rough seas.

This weather pattern is likely to persist, with ongoing risks of flash floods and landslides in vulnerable areas. Residents are advised to take precautions and stay updated on weather forecasts.