According to the National Center for Hydro-Meteorological Forecasting, currently, the cold air mass is moving southward, compressing a low pressure trough with its axis at about 24 - 27 degrees north latitude.
Last night and early this morning (April 28), the Northern region, Thanh Hoa and Nghe An had scattered showers and thunderstorms, locally heavy rain. Rainfall from 7 pm on April 27 to 8 am on April 28 locally over 50mm such as the following monitoring station: Phinh Ho (Quang Ninh) 82mm, Yen Lap (Phu Tho) 51.2mm,...
The Northern region is affected by cold air compressing low pressure troughs, so from the evening of April 28 to the morning of April 29, it is forecast to have rain, moderate rain and scattered thunderstorms with rainfall from 20 - 40mm, locally heavy to very heavy rain over 100mm.
The North Central region during the day and night of April 29, is forecast to have scattered showers and thunderstorms with rainfall of 10 - 30mm, locally heavy rain over 50mm.
The meteorological agency warns that in thunderstorms, there is a possibility of tornadoes, lightning, hail and strong gusts of wind. The level of natural disaster risk due to tornadoes, lightning, hail is level 1. These phenomena can affect agricultural production, causing trees to fall, damage to houses, traffic works, infrastructure. Localized heavy rain may cause flash floods on small rivers and streams, landslides on slopes and flooding in low-lying areas.
According to Dr. Truong Ba Kien - Deputy Director of the Center for Meteorology and Climate Research, Institute of Meteorology, Hydrology, Environment and Marine Science, in interseas conditions, especially when late-season cold air intensifies interaction with low-lying hot and humid air masses, the two air masses have different natures, increasing atmospheric instability, convergence and vertical wind interruption.
Therefore, it helps maintain a strong upward flow and extend the lifespan of particles in the super-cold region, thereby increasing accretion efficiency and the ability to form ice rain" - Dr. Kien assessed.
According to this meteorologist researcher, usually March and April are the periods with the most hailfall in the year, due to the characteristic of seasonal transition, the dispute between two different gas masses.
In late-season cold air waves, thunderstorms can occur, especially in northern mountainous provinces - where there are very high terrain conditions and atmospheric instability, increasing the risk of hail.
However, it should be noted that hail is a phenomenon that can only warn of dangers, cannot be accurately predicted. Therefore, people need to be careful and proactively ensure safety when there is a warning of thunderstorms during the transitional season" - Mr. Kien advised.
The meteorological agency recommends that when there is a risk of thunderstorms, tornadoes, hail and strong gusts of wind, people should closely monitor warning bulletins and limit going out when the weather turns thunderstormy.
If you are outdoors, you need to quickly find a safe shelter in a solid house, avoid standing under big trees, power poles, billboards or temporary structures.
When it rains heavily, you should stay indoors, close the doors tightly, and stay away from glass doors to limit breakage and injury.
For strong gusts of wind, it is necessary to reinforce the roof, reinforce items that are easily blown away by the wind, and not stay near areas at risk of collapse.
In addition, turn off electrical devices when there is lightning, limit the use of phones outdoors to reduce the risk of being struck by lightning.
