What air mass causes droughts?
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 kind of air mass would be warm and dry?
tropical air masses
What 2 air masses create the dry line?
Also called a “Dew Point Front”, sharp changes in dew point temperature can be observed across a dry line. Dry lines are most commonly found just east of the Rocky Mountains, separating a warm moist air mass to the east from a hot dry air mass to the west.
What are the four weather effects of air masses?
Similarly, you would probably expect arctic and polar air masses to be cold and tropical air masses to be hot. Put together, you can have dry, cool air (cA or cP); moist, cool air (mA or mP); dry, warm air (cT); or moist, warm air (mT). Air masses are not stationary, and their movement affects weather.
What happens when air masses meet?
When two air masses meet together, the boundary between the two is called a weather front. At a front, the two air masses have different densities, based on temperature, and do not easily mix. One air mass is lifted above the other, creating a low pressure zone.
Why do air masses move?
Winds and air currents cause air masses to move. Moving air masses cause changes in the weather. A front forms at the boundary between two air masses. Types of fronts include cold, warm, occluded, and stationary fronts.
What happens when two of the same air masses meet?
Air masses do not usually mix. So, when two different air masses meet, a boundary is formed. The boundary between two air masses is called a front. Weather at a front is usually cloudy and stormy.
What causes air masses to move around?
Air masses are large bodies of air that have similar temperature and humidity. These air masses are moved around the atmosphere by prevailing winds that blow in one direction. At the boundaries between air masses, weather fronts form. Weather fronts cause changes in the weather such as rain, storms and wind.
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.
What is the difference between an air mass and a front?
An air mass is a body of air with a relatively constant temperature and moisture content over a significant altitude. Air masses typically cover hundreds, thousands, or millions of square kilometers. A front is the boundary at which two air masses of different temperature and moisture content meet.
What air mass has the most moisture?
maritime air masses
What are two conditions you need for air mass formation?
What conditions are necessary for an air mass to form? It must stay over a land or sea surface long enough to acquire the temp/humidity/stability characteristics of the surface below. They are associated with source regions, they must be extensive, physically uniform, and have stationary air.
What causes an air mass to have a high pressure?
High pressure areas are usually caused by air masses being cooled, either from below (for instance, the subtropical high pressure zones that form over relatively cool ocean waters to the west of Califormia, Africa, and South America), or from above as infrared cooling of winter air masses over land exceeds the warming …
Do air masses compress as they rise?
Compression of the air mass is accompanied by an increase in temperature. Because warmer air is less dense than cooler air, warmer air rises. Counter-intuitively, moist air is also lighter than less humid air.
What happens to an air mass as it cools?
When a warmer air mass travels over colder ground, the bottom layer of air cools and, because of its high density, is trapped near the ground. In general, cold air masses tend to flow toward the equator and warm air masses tend to flow toward the poles. Air masses are slowly pushed along by high-level winds.