This afternoon, March 31, the National Center for Hydro-Meteorological Forecasting said that currently, in the north, there is a weak cold air mass moving southward, compressing a low pressure trough with its axis at about 23 - 26 degrees north latitude.
Mr. Nguyen Huu Thanh - Deputy Head of Weather Forecast Department, National Center for Hydro-Meteorological Forecasting provides information and forecasts from the night of March 31 to the morning of April 1, due to the influence of cold air compressing low pressure troughs, the Northern region (except Dien Bien, Lai Chau) will have scattered showers and thunderstorms with rainfall from 10 - 20mm, locally heavy rain over 40mm.
According to Mr. Thanh, thunderstorms are likely to occur with tornadoes, lightning, hail and strong gusts of wind. Localized heavy rain is likely to cause flash floods on small rivers and streams, landslides on slopes and flooding in low-lying areas.
On April 1st, widespread hot weather will end in the Northwest region and from Nghe An to Quang Ngai; the North will turn cool.
Regarding sea weather, from the night of March 31, in the Gulf of Tonkin, the wind will turn Northeast at level 4 - 5 and there will be showers and thunderstorms. In thunderstorms, there is a possibility of tornadoes and strong gusts of wind.
In recent rainstorms in many northern provinces and cities, dangerous phenomena have appeared. In the early morning of March 30, 2 ice rains appeared in Viet Hung ward (Hanoi). The rain time was short but the intensity of the rain was quite strong. Previously, in the afternoon of March 29, ice rain also appeared in Son Tay ward (Hanoi). Stones the size of fingertips, continuously falling down for about 15 - 20 minutes.
Regarding this weather phenomenon, according to Dr. Truong Ba Kien - Deputy Director of the Center for Meteorology and Climate Research - Institute of Meteorology, Hydrology, Environment and Marine Science, the continuous appearance of hail and thunderstorms in the second half of March is consistent with the climate law.
Dr. Truong Ba Kien analyzed that in a year there are two main seasonal transition periods: transition from spring to summer, from summer, autumn to winter.
These are periods of risk of extreme weather phenomena such as thunderstorms, tornadoes, hail,..." - Mr. Kien said.
According to meteorologists, the reason is that the transitional period is the transitional period between large-scale circulation systems, with the dispute of two gas masses with completely different characteristics.
For example, in March, the weather changes from cold air of winter to warm air of summer. The interaction between two air masses of opposite nature, one hot and humid and one dry and cold, easily triggers thunderstorms, tornadoes and hail" - Dr. Truong Ba Kien analyzed.
