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The frontal activity is invariably associated with cloudiness and precipitation because of ascent of warm air which cools down adiabatically, condenses and causes rainfall.Wind Shift: A change in wind direction of 45 degrees or more in less than 15 minutes with sustained wind speeds of 10 knots or more throughout the wind shift. Front experiences wind shift, since the wind motion is a function of pressure gradient and Coriolis force.With a sudden change in temperature through a front, there is a change in pressure also.

The temperature contrast influences the thickness of frontal zone in an inversely proportional manner, i.e., two air masses with higher temperature difference do not merge readily.As the more “aggressive” air mass advances at the expense of the other, some mixing of the two occurs within the frontal zone, but for the most part, the air masses retain their separate identities as one is displaced by the other.The frontal concept was developed by Norwegian meteorologists during World War I, and the term front was coined because these scientists considered the clash between unlike air masses to be analogous to a confrontation between opposing armies along a battlefront.When unlike air masses meet, the two air masses don’t merge readily due to the effect of the converging atmospheric circulation, relatively low diffusion coefficient, and low thermal conductivity.Front is a three-dimensional boundary zone formed between two converging air masses with different physical properties (temperature, humidity, density, etc.).They are uncommon (unusual) in tropical and polar regions. Fronts are the typical features of midlatitudes weather ( temperate region: 30° – 65° N and S).Fronts are actually zones of transition, but sometimes the transition zone, called a frontal zone, can be quite sharp. Fronts are boundaries between air masses of different temperatures.