According to the National Center for Hydro-Meteorological Forecasting, hot weather in the North will continue until around April 14, while the North Central region lasts until April 16. After that, cold air begins to affect, causing temperatures to gradually decrease. From April 17, thunderstorms may appear in most areas, except for the South Central region with little rain.
Forecast for the 11th and 12th of April is the peak of the first hot spell of this year, with temperatures in Hanoi and the surrounding areas possibly reaching 38-39 degrees Celsius, while western Nghe An and Ha Tinh record levels of 40-41 degrees Celsius. Widespread hot weather, accompanied by low humidity of only 35-45%, causing a feeling of dryness and stuffiness.
Notably, during peak hot weather, air pressure in many areas such as Hanoi, the Northern Delta, Thanh Hoa, Nghe An, Ha Tinh, Quang Tri may drop below 999hPa in the afternoon, creating a clear feeling of stuffiness.
The meteorological agency forecasts that the appearance of cold air after a long period of hot weather will increase the risk of extreme weather. Heated soil will create vertical air flows, when encountering cold air, it will condense strongly, forming thunderstorms and possibly developing into hail.
Warning on April 16 and 17, the risk of thunderstorms and hail is very high in the mountainous and midland areas of the Northern region, as well as the Northwest Central region. First rains of the season after hot weather can evaporate methane and sulfur from the soil. These are toxic gases, people should limit going out when there are thunderstorms.
Not only the North, the Central region is also experiencing a severe heat wave. In Nghe An, temperature stations recorded temperatures above 41 degrees Celsius in Con Cuong and Do Luong, while Huong Khe (Ha Tinh) also exceeded 40 degrees Celsius. The foehn wind effect combined with the hot low pressure area in the West has made this area a "hot pan" for many consecutive days.
The meteorological agency said that the actual outdoor temperature may be 2-4 degrees Celsius higher than forecast due to the influence of heat-absorbing surfaces such as concrete and asphalt roads. This increases the risk of heat shock, water loss and exhaustion when exposed to high temperatures for a long time.
Intense heat combined with low humidity also increases the risk of fire and explosion, especially in residential areas due to increased electricity demand, as well as the risk of forest fires in many localities.
People and tourists need to limit going out during peak heat and supplement with enough water.
Closely monitor forecast bulletins when cold air begins to affect to proactively prevent thunderstorms, lightning and hail.
