cT — Continental tropical air usually only influences the US in summertime as warm, dry air is pumped up off of the Mexican Plateau. It is usually fairly stable and dry, and if it becomes stagnant over the midwest, results in a drought.
What air mass has dry conditions?
Air masses are classified on weather maps using two or three letters. A lowercase letter describes the amount of moisture in the air mass: m for maritime (moist) and c for continental (dry).
What air mass has the driest air?
Continental polar (cP) or continental arctic (cA) air masses are cold, dry, and stable. These air masses originate over northern Canada and Alaska as a result of radiational cooling.
What air mass causes precipitation?
The frontal zone slopes up and over the colder air mass ahead of it. Warm air rides along the front (up and over the cold air mass), cooling as it rises, producing clouds and precipitation in advance of the surface warm front.
Which type of air mass is most responsible for droughts?
Because it contains little moisture, continental tropical air is often responsible for drought conditions. 1. Most Maritime polar air masses that affect the United States are formed in the north Pacific Ocean.
What are the six types of air masses?
This gives us six total types of air masses on Earth: maritime arctic (mA), maritime polar (mP), maritime tropical (mT); and continental arctic (cA), continental polar (cP) and continental tropical (cT) .
Which is the coldest air mass?
The coldest air masses are Arctic air masses . These air masses originate at the poles of the Earth in Greenland and Antarctica. Since these areas of...
Why is there no such thing as a maritime Arctic air mass?
But mA-type (maritime Arctic) does not exist . Continental Polar air masses form over large, high- latitude land masses, such as northern Canada or Siberia. cP air masses are cold and extremely dry. Wintertime cooling over these land areas cause the atmosphere to become very stable (even inversion).
Which air mass is the most dense?
The air of cold air masses is more dense than warmer air masses. Therefore, as these cold air masses move, the dense air undercuts the warmer air masses forcing the warm air up and over the colder air causing it to rise into the atmosphere.
What are the 5 types of air mass?
These are Polar (cold), Arctic (very cold), Equatorial (warm and very moist), and Tropical (warm). In the United States the major air mass types are typically continental Polar, maritime Polar, continental Tropical, and maritime Tropical .
Which air mass is the coldest and driest?
continental-Arctic (cA) : Winter’s most frigid air masses. cA air masses are the coldest of the cold and the driest of the dry.
What happens when two air masses crash into each other?
When two different air masses come into contact, they don’t mix. They push against each other along a line called a front . ... As it rises, the warm air cools rapidly. This configuration, called a cold front, gives rise to cumulonimbus clouds, often associated with heavy precipitation and storms.
Where does an air mass get its humidity from?
Air masses are slowly pushed along by high-level winds , when an air mass moves over a new region, it shares its temperature and humidity with that region. So the temperature and humidity of a particular location depends partly on the characteristics of the air mass that sits over it.
What causes air mass to move around?
An air mass is a large body of air that has about the same conditions throughout. Air masses take on the conditions of the area where they form. Winds and air currents cause air masses to move.
What happens when an air mass is heated?
As the molecules heat and move faster, they are moving apart. So air, like most other substances, expands when heated and contracts when cooled . Because there is more space between the molecules, the air is less dense than the surrounding matter and the hot air floats upward.
What would weather be like if air masses did not move?
At a stationary front the air masses do not move (Figure below). A front may become stationary if an air mass is stopped by a barrier, such as a mountain range. A stationary front may bring days of rain, drizzle, and fog.
