Tornadoes approach rapidly, and it is therefore almost impossible for those who happen to be in their path to escape their violence.
A tornado at sea is termed a water spout.
RAINFALL
You will recall a preceding statement that evaporated humidity turns into water when it becomes cool below a certain point. (See page [14], Effect of the Sun.) A given amount of air will hold a certain amount of moisture. For example, let us assume that a cubic foot of air (see Fig. [11]) is saturated, that is, it is holding all the water it will retain. Now if this cubic foot of air is cooled, it will contract, and as a result there will not be enough room to hold both the air and moisture, so the excess moisture will leak out. (See Fig. [12].) The result of this reduction in temperature causes precipitation, simply because the air cannot sustain the water that is in it. Therefor, at any time when moisture in the air has reached the point of saturation and a chilling takes place, due to the air becoming cold, rain follows. This may happen as a result of air rising into higher places or cooler levels, or through its contact with cooler surfaces.
WHY WE GET SUCH HEAVY RAINFALLS SOMETIMES AROUND MOUNTAINS
The air becomes thoroughly saturated. When air is comparatively warm, it will expand, and this air, which is heavily saturated is brought up by breezes onto the mountain range, which is cold, causing the air to lose its heat and contract and really force the water out of the air. The same principle applies to sea breezes bringing rain.
WINDS
Winds are caused as a result of differences in temperature between the various layers of the atmosphere. A certain amount of air becomes heated and rises, and as explained before, expands. As the air expands, it becomes lighter, and because it is light it goes upward toward higher regions. It also flows from hot to cold countries. A good illustration of this is the sea breezes. If you have lived around the seashore in the summer time, you will have observed that during the hot part of the day the winds generally blow from the sea toward the land. At night the direction of the wind is reversed, that is, it blows from the land to the sea. Why? Because the land during the day retains its heat, while the water diffuses it. What is the result? The air on the land expands, becomes light. The air over the water being cool, it does not expand, and the result is that it presses toward the land. At night the land loses its heat more rapidly than the water, so that it is not long before the land is cooler than the water, and when this happens, the air over the land, which has become cooler, presses seaward.
KINDS OF WINDS
Mountain Breezes: Caused by the heating and cooling of the hills and valleys.