The air close to the ground is warmer than the air higher up. Warm air is lighter than cold light, and therefore rises. There is a strong upward flow of moist, warm air. If the warm air has ascended to a height or 10 kilometer cools the air quickly because the air in the environment is much colder. This again created water droplets and small ice particles. The ice particles are larger and grow into hailstones. These hail stones are negatively charged and they are so heavy at the bottom of the cloud to come down. The strong negative charge of the bottom of the cloud shock (like magnets) the negative particles in the Earth's surface, which thus descend deeper into the soil. The top layer of the earth is thus positively charged. Now is the following situation:
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For a cyclist and a force 7 moped is quite annoying to mention, in a stormy wind (force 8) is difficult to keep your balance. With a wind 9 or higher is virtually impossible and bicycles are young children quickly. In force 10 or higher can barely stand one adult pedestrian. Even trucks and cars with trailers and caravans, face very much hindered by the treacherous winds of the stormy especially when the wind is high. The wind speed in Breda (October 28, 2000) was showery difference between the lowest and highest wind speed at a given time (see registration link).
A storm is particularly disruptive when society-at the time of the storm many people on his leg. The storm of January 25, 1990 took 17 people died because the storm at the end of the afternoon during the busy evening rush occurred.
The KNMI has for some time the weather alert was created. In a (projected) wind force 10 or higher or very heavy winds it is issued.
The damage to trees and buildings depends on the strength thereof. In trees, the root depth and age affect whether the tree falls down or breaks up or remains. The flexibility of the trunk and branches per tree species are different. It is also the stormy weather that proved fatal for the tree. Even trees in a forest can therefore deal by not enough between the winds from their initial position to recover. Considerable damage to buildings generally to enter into force 10 or higher. This is largely determined by the type and construction of the house. Houses with roof tiles are an especially easy prey when they are released into the countryside. Tiles falling from the roof, usually side with the wind but on the other side of the roof where often a strong suction occurs and thus the tiles of the roof sucks.