Mioara ŞIŞU, Vlad D. MIRCOV, Simona NITA
One of the phenomena associated with atmospheric instability and a negative impact both in daily life, and in pursuit of activities related to agriculture, is the hail. As a type of rainfall, hail consists of ice particles with a diameter of between 5 and 50 mm, sometimes even larger. It emerges from Cumulonimbus clouds and it is usually accompanied by rain showers, lightning and wind gust. Hail is a characteristic phenomenon for the warm period of the year and is formed especially in cold front passage (very active ones) over overheated surfaces. Thermal non-homogeneity in the lower layers of air, or roughness of underlying surfaces, generate upward movement of air, lead to the formation of so-called "convection cells", whose characteristics are essential in hail occurrence. Since in many cases damages are significant and it is difficult to say in the short-range forecasts which areas will be affected by this phenomenon, forecast for the immediate meteorological phenomena and anti-hail measures have a particularly important role. This work presents two synoptic situations that have led to hail in the Western Plain area and which resulted in serious damage. For each of the two cases, a presentation of the synoptic and mesoscale settings (with image examples for some important parameters), followed by a description of the general appearance of the weather, the context in which there were severe weather phenomena, in this case - the production of hail and an estimation of damage. In the end of the work, there is a short presentation of anti-hail methods that can be taken both in our country and at European level.
hail, Cumulonimbus clouds, updrafts, atmospheric instability, anti-hail systems
Presentation: oral