Air masses and fronts
There are two distinctive fronts, a warm front and a cold front. A cold front is formed whenever cool air replaces the warm air. A warm front is formed when warm air replaces the cold air. A cold fronts normally travel northwest to southeast. The warm front normally moves from southwest to northwest. Warm fronts are represented by a solid line with semicircles pointing toward the cold air and the direction of movement. Cold fronts are represented by a solid line with triangles that point toward the warmer air and they also point toward the direction of the movement.
An air mass is a large pocket of air that has three distinctive characteristics,
1. around 1,000 m long and wide (Big)
2. must have uniform and consistent makeup
3. must be physically bound togetherThere are 5 different types of air masses. They are continental arctic, (cA) Continental Polar, (cP) Maritime Polar, (mP) Maritime Tropical, (mT) and Continental Tropical (cT). Each air mass has two different names for it. The Tropical and Polar show that the temperature is warm or dry, and it shows if it is formed near the equator or near the poles. The Tropical is warm and is formed near the equator. Whereas the the Polar is cold and is formed near the poles of the Earth. If an air mass is a Maritime or Continental air mass, then it shows if it is wet or dry and if it forms over land or over water. If the Air mass is a Maritime air mass, then it is wet and it forms over water. If the air mass is a continental air mass, then it is dry and is formed over land. For example: a cT is dry, forms over land, is formed near the equator, and is warm. When the letters “K” or “W” are on the end of the air mass, “K” means that the air moving is colder than the air on the surface. “W” means that the air moving is warmer than the surface temperature.