The hail storm is a form of precipitation that falls from the sky as pellets of ice. The pellets can range in size from small pea-sized pellets, to hailstones as large as grapefruits. Hail is especially damaging to crops.

The risk of hail storm is especially high in ares with school for children. In this case is important to differentiate the risk of accidents caused by the impact and risk exposure. The probability of hail (PH), the damage caused by the rain that depends on the size of the ice (DG) and the value of what is at risk, for example the population of children (VR). The calculation for these three major components of risk that this phenomenon faces indicates the “severity” or gravity of the loss, can be expressed:

Expected Loss = PH * DG * VR

Often general forecasts from the various agencies lack the detail required to predict hailstorms 24 hours to up to a week ahead. It is possible of course possible to provide such assessment of hail risk with an accuracy of up to 95% particularly on the day prior to the actual day. Nevertheless, more often than not, a study of special models and their variable behavior can provide sufficient lead time forecasts for those involved in various industries immediately associated with or affected by hail to prepare for the onslaught of hailstorms.

A example that is the sudden hail storm that happens in city Russian of Novosibirsk in July of 2014. Sudden a cold snap to 20 degrees (from 41 to 21), plus strong winds and hail.

We may not be able to stop hailstorms, but effective preparation can reduce to risk to life. and property.