1w051a CDC Volume 1

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1. Which orographic cloud resembles an almond or a fish?

Explanation

Lenticular clouds are formed when moist air flows over a mountain or hill and creates a series of standing waves. These clouds are lens-shaped and often have a smooth, rounded appearance, resembling an almond or a fish. They are commonly found in the lee of mountains and can indicate strong winds and turbulence in the atmosphere.

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About This Quiz
1w051a CDC Volume 1 - Quiz

This quiz, titled '1W051A CDC Volume 1', assesses knowledge on atmospheric conditions, focusing on temperature variations, ozone formation, and water vapor effects in different atmospheric layers. It is designed for learners aiming to understand basic meteorological concepts critical for aerospace studies.

2. "Clouds or obscuring phenomena that have bases at the same approximate level" is the definition of

Explanation

The definition provided, "Clouds or obscuring phenomena that have bases at the same approximate level," describes a layer. A layer refers to a type of cloud formation where clouds or other obscuring phenomena are present at the same height or altitude. This term is commonly used in meteorology to describe a specific type of cloud formation in the atmosphere.

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3. A decrease of mass in a column of air will cause the surface pressure to

Explanation

When there is a decrease in mass in a column of air, it means that there is less air present in that column. As a result, the air molecules are less densely packed, leading to a decrease in pressure. This decrease in mass causes a decrease in the surface pressure.

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4. How do you report prevailing visibility at US stations and overseas stations?

Explanation

The prevailing visibility at US stations is reported in statute miles, while at overseas stations it is reported in meters. This means that in the US, visibility is measured and reported in miles, whereas in other countries it is measured and reported in meters.

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5. To properly report the visibility for more than one sector, you would list the sectors in a

Explanation

To properly report the visibility for more than one sector, it is important to list the sectors in a clockwise direction starting with the northernmost sector. This ensures consistency and clarity in reporting the visibility for each sector. By following a clockwise direction, it becomes easier to identify and communicate the visibility for each sector in a systematic manner. Starting with the northernmost sector also helps in maintaining a logical order while reporting the visibility for multiple sectors.

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6. What is the intensity of snow which restricts visibility to less than 1/4 mile?

Explanation

The correct answer is "Heavy" because heavy snowfall significantly reduces visibility to less than 1/4 mile. This means that the snow is falling at a high rate and accumulating quickly, making it difficult to see and navigate through.

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7. What air mass forms over land only during the summer?

Explanation

Located on page 1-54

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8. "Jet fingers"

Explanation

Located on page 1-37

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9. An increase of mass in a column of air will cause the surface pressure to

Explanation

When the mass of a column of air increases, it means that there is more air in that column. As a result, the air molecules become more densely packed, leading to an increase in pressure. This is because the weight of the additional air molecules exerts a greater force on the surface, causing the surface pressure to increase.

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10. When the central pressure of an anticyclone is rising, you can infer the anticyclone is

Explanation

When the central pressure of an anticyclone is rising, it indicates that the air in the anticyclone is becoming denser and sinking, which leads to the strengthening and expansion of the anticyclone. This process is known as building. Therefore, the correct answer is building.

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11. Unstable waves are classified as

Explanation

Unstable waves are classified as baroclinic lows. Baroclinic refers to the condition where there is a gradient in temperature or density within a fluid. In the case of unstable waves, there is a significant difference in temperature or density between adjacent air masses, leading to the formation of low-pressure systems. These baroclinic lows are characterized by strong vertical wind shear and can cause severe weather conditions such as storms and cyclones.

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12. The distinguishing feature of any tornadic activity is

Explanation

Tornadic activity is characterized by the presence of a funnel-shaped appendage that hangs from the base of the cloud. This funnel-shaped appendage is commonly known as a tornado. It is formed when a rotating column of air extends from the base of a cumulonimbus cloud to the ground. This feature is distinct and easily recognizable, making it the distinguishing feature of tornadic activity. The other options, such as intense thunderstorm activity, wind gusts over 35 knots, and cumulonimbus mammatus clouds, may be associated with tornadic activity but are not unique to it.

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13. The best way to distinguish stratocumulus from altocumulus clouds is to use

Explanation

The best way to distinguish stratocumulus from altocumulus clouds is by looking at the size of the elements. Stratocumulus clouds are characterized by larger, more rounded elements, while altocumulus clouds have smaller, more fragmented elements. By observing the size of the cloud elements, one can differentiate between these two cloud types.

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14. In the life cycle of a low, the wave will reach its maximum intensity in the

Explanation

In the life cycle of a low, the wave will reach its maximum intensity in the mature stage. This is because during this stage, the low pressure system is fully developed and has reached its peak strength. The associated weather conditions, such as strong winds and heavy precipitation, are at their most intense during this stage. After the mature stage, the low pressure system will gradually weaken and dissipate. Therefore, the correct answer is the mature stage.

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15. What causes a surface high to build during the self-development process?

Explanation

During the self-development process, a surface high builds due to convergence aloft. Convergence aloft refers to the horizontal movement of air towards a central point in the upper levels of the atmosphere. This convergence leads to the sinking of air, which in turn creates high pressure at the surface. As air sinks, it warms and becomes denser, resulting in the formation of a high-pressure system. Therefore, convergence aloft is the cause of a surface high during the self-development process.

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16. A high-pressure system undergoes anticyclolysis when the clockwise circulation area

Explanation

Anticyclolysis refers to the dissipation or weakening of a high-pressure system. This occurs when the clockwise circulation area of the system decreases or disappears. In other words, the system loses its organized circulation pattern, resulting in a decrease or complete disappearance of the clockwise flow. This can happen due to various factors such as changes in atmospheric conditions or interactions with other weather systems.

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17. Above 13 miles, the radiation from the sun breaks down the oxygen in the atmosphere into

Explanation

Located on page 1-4

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18. A thunderstorm officially ends

Explanation

A thunderstorm officially ends fifteen minutes after the last occurrence of thunder, hail, or lightning. This means that once there is no more thunder, hail, or lightning activity for fifteen minutes, the storm is considered to be over. This time period allows for any potential lingering activity to completely dissipate before declaring the end of the storm.

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19. Which high cloud classification is also referred to as a mackerel sky?

Explanation

Cirrocumulus clouds are often referred to as a mackerel sky due to their appearance, which resembles the scales of a fish or the patterns on a mackerel. These clouds are high-level clouds, composed of small white or gray patches or ripples, and are usually seen in fair weather conditions. They are formed by the rising of moist air in the upper atmosphere, which then condenses and freezes into ice crystals, creating the distinct mackerel-like pattern. Therefore, Cirrocumulus-H9 is the correct answer.

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20. It is winter. A cPk air mass is moving over the great lakes. In this situation, the southern shores of the Great Lakes will experience

Explanation

Located on page 1-59

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21. The three circulation cells in the three-cell circulation theory are

Explanation

Located on page 1-13

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22. In a warm frontal occlusion, the coldest air is found

Explanation

In a warm frontal occlusion, the coldest air is found ahead of the warm front. This is because warm frontal occlusions occur when a warm air mass moves into an area of colder air. As the warm air rises over the colder air, it cools and condenses, creating clouds and precipitation. The coldest air is typically found ahead of the warm front, where the warm air is still rising and the cold air is being pushed up and over it.

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23. The simplest method for locating the 500 millibar frontal zone is to

Explanation

Located on page 1-35

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24. If you throw a ball towards a stationary target from the window of a speeding vehicle, coriolis force will cause the ball to miss the target

Explanation

Located on page 1-15

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25. The damper effect is comprised of upper-level

Explanation

The damper effect refers to a meteorological phenomenon where the convergence of air masses and the presence of high surface pressure result in the suppression or reduction of atmospheric motion. In this case, the correct answer is convergence and surface high pressure, as it accurately describes the conditions required for the damper effect to occur. When air masses converge and there is high pressure at the surface, it leads to stable atmospheric conditions and limits the vertical motion of air, dampening any potential disturbances or weather systems.

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26. A low-pressure system undergoing cyclogenesis is said to be

Explanation

When a low-pressure system undergoes cyclogenesis, it means that it is forming or intensifying. The term "forming" refers to the process of a low-pressure system developing and becoming more organized, while "deepening" indicates that the system is strengthening and the central pressure is decreasing. Therefore, the correct answer is "forming or deepening."

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27. What type of precipitation might you observe with clear skies?

Explanation

Clear skies typically indicate a lack of clouds, which means that there is little moisture in the air. In such conditions, it is unlikely to observe precipitation like snow, ice pellets, or snow grains, as these require the presence of clouds. However, ice crystals can still form in the atmosphere even without clouds, usually due to very cold temperatures. Therefore, ice crystals would be the most plausible type of precipitation to observe with clear skies.

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28. Precipitation is reported to the nearest

Explanation

Precipitation is reported to the nearest 0.01 of an inch. This means that when measuring the amount of precipitation, the value is rounded to the nearest hundredth of an inch. This level of precision allows for more accurate reporting of rainfall or snowfall measurements.

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29. What air mass calssification signifies an unstable, maritime tropical air mass that is colder than the surface it is moving over?

Explanation

Located on page 1-51

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30. What air mass classification signifies a stable, continental polar air mass that is warmer than the surface it is moving over?

Explanation

Located on page 1-51

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31. Continental tropical air masses are usually associated with

Explanation

Located on page 1-61

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32. When an inactive front passes your station, the dew points will

Explanation

When an inactive front passes a station, the dew points decrease sharply with the passage. This is because an inactive front is associated with cooler air replacing warmer air. As the front moves through, the cooler air displaces the warmer air, causing the dew points to decrease rapidly.

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33. Centrifugal force will increase when there is a decrease in

Explanation

Located on page 1-15

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34. For observing purposes, five hydrometers are considered to be obstructions to vision. They include mist, fog, blowing snow,

Explanation

The correct answer is freezing fog and blowing spray. These two weather conditions, freezing fog and blowing spray, can obstruct vision and make it difficult to see clearly. Mist, fog, blowing snow, and blowing sand are also mentioned in the question, but they are not considered obstructions to vision.

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35. How many degrees centigrade does the temperature decrease per 1,000 meters of altitude in the troposphere?

Explanation

Located on page 1-3

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36. With the passage of a cold front in the Northern Hemisphere, the horizontal wind direction will

Explanation

When a cold front passes through the Northern Hemisphere, the wind direction shifts in a clockwise direction. This is because cold fronts typically bring cooler air from the north, which causes the wind to rotate in a clockwise direction around the low-pressure system associated with the front. As the cold air replaces the warm air, the wind shifts from its previous direction to a more clockwise direction.

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37. What factors must a region possess in order to facilitate air mass formation?

Explanation

Located on page 1-49

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38. The driving mechanism that is mainly responsible for the earth's large-scale atmospheric circulations is the

Explanation

Located on page 1-12

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39. In a cold occlusion, the coldest air is found

Explanation

In a cold occlusion, the coldest air is found behind the cold front. This is because in a cold occlusion, a cold front overtakes a warm front, causing the colder air to push underneath the warmer air. As the cold front moves forward, it brings the coldest air with it, creating a boundary between the colder air behind the front and the warmer air ahead of it. Therefore, the coldest air is located behind the cold front in a cold occlusion.

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40. In relation to the jet core, the greatest vertical wind shear is usually located

Explanation

located on page 1-32

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41. The  most desirable night-visibility markers are

Explanation

Unfocused lights are the most desirable night-visibility markers because they provide a broader and more diffuse illumination, which helps to enhance visibility in low light conditions. Unlike focused high-intensity lights that have a narrow beam, unfocused lights spread the light over a wider area, making it easier to see and be seen in the dark. Dark-colored objects may blend into the background and be difficult to distinguish, while light-colored objects may not provide enough contrast in low light situations. Therefore, unfocused lights are the best option for maximizing visibility at night.

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42. The three main forms of precipitation are liquid,

Explanation

The correct answer is "freezing, and frozen." This answer accurately identifies the two main forms of precipitation. Freezing refers to when precipitation falls as liquid but freezes upon contact with a surface, such as freezing rain or freezing drizzle. Frozen refers to precipitation that falls in the form of ice crystals, such as snow or hail.

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43. Which type of obstruction to vision is classified as a lithometer?

Explanation

A lithometer is a device used to measure the opacity or density of smoke. Therefore, smoke is classified as a lithometer because it obstructs vision and can be measured using this device. Fog, ash, and spray are not specifically classified as lithometers, although they can also obstruct vision.

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44. Which is a calculated sea-level pressure in inches of mercury?

Explanation

The altimeter setting is a calculated sea-level pressure in inches of mercury. It is used to adjust the altimeter reading to reflect the current atmospheric pressure at sea level, allowing for accurate altitude measurements. The altimeter setting takes into account factors such as temperature and humidity to provide a standardized pressure reference for pilots and meteorologists.

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45. Wind observing equipment is oriented to

Explanation

Wind observing equipment is oriented to magnetic north because the Earth's magnetic field affects the direction of the wind. Magnetic north is the direction towards the Earth's magnetic north pole, which is slightly different from true north. By aligning the equipment with magnetic north, it allows for accurate measurement and recording of wind direction relative to the Earth's magnetic field. This is important for various applications such as weather forecasting, aviation, and navigation.

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46. Which force is the "equal and opposite reaction" to the center-seeking force?

Explanation

Located on page 1-14

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47. What color balloon would you use to determine the ceiling heights of thin clouds?

Explanation

Red is the correct answer because red light has a longer wavelength compared to other colors, making it less likely to be scattered by small particles in the atmosphere. This allows red light to penetrate thin clouds more effectively, making it easier to determine the height of the cloud ceiling.

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48. The jet core that is located between the midlatitude and the tropical tropoause's is called the

Explanation

Located on page 1-35

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49. Anticyclogenesis typically occurs at, and just downstream from, long-wave

Explanation

Anticyclogenesis refers to the formation of an anticyclone, which is a high-pressure system characterized by descending air and clockwise rotation in the Northern Hemisphere. This process typically occurs at, and just downstream from, long-wave ridges. Confluent flow aloft refers to the convergence of air masses, where the wind flow comes together. In the context of anticyclogenesis, ridges under confluent flow aloft create favorable conditions for the development of high-pressure systems. Therefore, the correct answer is "ridges under confluent flow aloft."

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50. A sudden increase of wind speed of at least 16 knots and a sustained average of 22 knots (or more) that is maintained for at least 1 minute before the speed diminishes is called a

Explanation

A sudden increase in wind speed of at least 16 knots and a sustained average of 22 knots (or more) that lasts for at least 1 minute before the speed diminishes is known as a squall. A squall is a short-lived, intense burst of wind that can be accompanied by heavy rain or snow. It is characterized by a rapid and significant increase in wind speed, often causing hazardous conditions for maritime and aviation activities.

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51. Surface pressure changes are largely controlled by

Explanation

The correct answer is mass changes in the upper troposphere. Surface pressure changes are largely controlled by the movement of air masses in the atmosphere. When there are mass changes in the upper troposphere, it can lead to changes in the vertical distribution of air, which in turn affects the surface pressure. These mass changes can be caused by various factors such as the movement of weather systems, the convergence or divergence of air masses, and the vertical motion of air. Therefore, mass changes in the upper troposphere play a significant role in determining surface pressure patterns.

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52. What causes the surface low to deepen during the self-development process?

Explanation

During the self-development process, the surface low deepens due to divergence aloft. Divergence aloft refers to the horizontal movement of air away from a central point in the upper levels of the atmosphere. This movement creates a vertical stretching of the air column, which leads to a decrease in surface pressure. As the surface pressure decreases, the low-pressure system intensifies and deepens. Therefore, divergence aloft is the cause of the surface low deepening during the self-development process.

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53. Advection transfers temperature

Explanation

Located on page 1-48

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54. The average slope of a cold front is

Explanation

The correct answer is 1/30 to 1/100. The average slope of a cold front refers to the rate at which the front rises or falls over a given distance. A slope of 1/30 to 1/100 indicates a gradual incline or decline, suggesting a smooth transition between warm and cold air masses. This range is commonly observed in cold fronts, where the leading edge of a mass of cold air displaces warmer air, causing weather changes.

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55. Which heat transfer process involves the transfer of energy by molecular motion from hot to cold objects?

Explanation

Located on page 1-48

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56. The areas of low pressure that correspond to the belt of low pressure at 60°N created by the 3-cell circulation are the

Explanation

Located on page 1-26

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57. The primary cause of surface pressure changes for a dynamic low is net

Explanation

Divergence aloft refers to the horizontal movement of air away from a specific location in the upper atmosphere. In the case of a dynamic low, this divergence aloft causes a decrease in air pressure at the surface. As the air moves away from the low-pressure system, it creates a void that is filled by air from higher pressure areas, resulting in a decrease in surface pressure. Therefore, divergence aloft is the primary cause of surface pressure changes in a dynamic low.

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58. How many stages are there in the life cycle of a low?

Explanation

The correct answer is Five. This indicates that there are five stages in the life cycle of a low. However, without further context or information, it is not possible to provide a detailed explanation of what these stages are.

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59. The width of the jet stream core is approximately equal to the

Explanation

Located on page 1-35

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60. What will the jet stream usually do when a cold, moving, polar high stagnates and begins to warm?

Explanation

Located on page 1-40

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61. Which is true of water vapor in the atmosphere?

Explanation

Located on page 1-4

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62. Horizontal divergence within an air mass will

Explanation

Horizontal divergence within an air mass refers to the spreading out of air horizontally. This spreading out causes the air column to vertically contract, meaning it becomes narrower in the vertical direction. As the air column contracts vertically, it then expands horizontally, resulting in a wider area of air. Therefore, the correct answer is that horizontal divergence within an air mass will vertically contract the original column of air and then expand it horizontally.

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63. Frontogenesis requires two adjacent air masses with

Explanation

Frontogenesis refers to the process of the formation or strengthening of a front, which is the boundary between two air masses with different properties. In order for frontogenesis to occur, the two air masses must have different densities, as stated in the correct answer. Additionally, a wind flow is necessary to bring these air masses together and create the necessary conditions for frontogenesis. Therefore, the correct answer states that frontogenesis requires different densities and a wind flow to bring the air masses together.

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64. Which low cloud type and classification is identified by the presence of a cirriform anvil?

Explanation

The correct answer is Cumulonimbus-L9. The presence of a cirriform anvil is characteristic of a cumulonimbus cloud. Cumulonimbus clouds are large, towering clouds that are associated with thunderstorms and can extend into the upper levels of the atmosphere. The cirriform anvil refers to the flat, spreading top of the cloud that resembles the shape of an anvil. Therefore, Cumulonimbus-L9 is the correct low cloud type and classification that is identified by the presence of a cirriform anvil.

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65. Blowing spray is reported only at sea stations near large bodies of water and when visibility at eye level is restricted to

Explanation

Blowing spray is reported only at sea stations near large bodies of water and when visibility at eye level is restricted to 9,000 meters or less. This means that blowing spray is observed when the visibility is reduced to 9,000 meters or less. The presence of blowing spray is an indication of rough sea conditions and strong winds, which can create hazardous conditions for maritime activities. Therefore, it is important to report blowing spray when visibility is reduced to 9,000 meters or less.

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66. A low dissipates after proceeding through its entire life cycle which ranges from the

Explanation

not-available-via-ai

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67. The weather characteristics of a particular month in a given locality are governed by

Explanation

Located on page 1-62

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68. Converging contours downstream of the jet stream will cause the jet to

Explanation

Located on page 1-37

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69. Coriolis force is created by

Explanation

Located on page 1-15

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70. After warm air with an unstable wave is pushed aloft and cuts off from a cyclone, the cyclone will become

Explanation

When warm air with an unstable wave is pushed aloft and cuts off from a cyclone, the cyclone will become barotropic and begin to fill. This means that the cyclone will lose its vertical temperature gradient and become more symmetric in terms of temperature distribution. As a result, the cyclone will weaken and fill in, meaning that it will decrease in intensity and fill with cooler air. This is in contrast to a baroclinic cyclone, which would maintain or intensify its temperature gradient and deepen instead of filling.

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71. Which process is most responsible for the slow formation of air masses in the polar region?

Explanation

Located on page 1-49

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72. A thunderstorm is present and occurring at your station. In addition, the local noise level is preventing you from hearing the thunderstorm. For observation purposes you would say

Explanation

not-available-via-ai

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73. When only high and middle clouds are associated with a warm front, the

Explanation

When only high and middle clouds are associated with a warm front, it indicates that the underlying cold air is dry. This is because high and middle clouds are composed of ice crystals and supercooled water droplets, which form in cold air. If the underlying cold air were moist, it would result in the formation of low-level clouds as well. However, since only high and middle clouds are present, it suggests that the overrunning warm air is dry.

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74. The force that is responsible for starting the horizontal movement of air over the earth's surface is

Explanation

Located on page 1-17

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75. The frontolytic processes are most effective

Explanation

Frontolytic processes refer to the mechanisms that weaken or dissipate fronts, which are boundaries between air masses with different characteristics. These processes are most effective in the lower layers of the atmosphere because this is where the majority of the atmospheric mixing and turbulence occur. In the lower layers, warm air rises and cold air sinks, creating instability and enhancing the interaction between air masses. This promotes the disruption of fronts and the dispersion of their associated weather systems. In contrast, the upper layers of the atmosphere are generally more stable and have less mixing, making frontolysis less effective.

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76. When using Petterssen's rule, the factors needed for cyclogenesis are upper-level

Explanation

Petterssen's rule states that for cyclogenesis, there needs to be divergence and a frontal zone where thermal advection is weak. Divergence refers to the horizontal movement of air away from a given point, which helps create low pressure. A frontal zone is an area where two air masses of different properties meet, often leading to the formation of weather systems. When thermal advection is weak, it means that the horizontal transport of heat is not significant, which allows the frontal zone to remain stable. Therefore, the correct answer is divergence and a frontal zone where thermal advection is weak.

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77. The best sources for identifying a frontal inversion are the

Explanation

The best sources for identifying a frontal inversion are the temperature and dew-point curves and the vertical wind distribution. A frontal inversion occurs when warm air is trapped beneath a layer of cooler air, causing a temperature inversion. By analyzing the temperature and dew-point curves, one can identify the presence of a frontal inversion. Additionally, the vertical wind distribution can provide further evidence of a frontal inversion, as it may show a stable layer of air preventing vertical mixing. Therefore, both the temperature and dew-point curves and the vertical wind distribution are crucial in identifying a frontal inversion.

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78. The two atmospheric gases most responsible for the absorption of incoming solar radiation are

Explanation

Located on page 1-9

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79. The stratosphere is characterized by

Explanation

Located on page 1-3

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80. Aloft, during the baroclinic instability process, the thermal wave and contour wave are 

Explanation

During the baroclinic instability process, the thermal wave and contour wave are out-of-phase, meaning that they are not synchronized in their oscillations. This means that when the thermal wave is at its peak, the contour wave is at its trough, and vice versa. Additionally, cold-air advection occurs into the contour trough, which means that colder air is moving into the region of lower pressure.

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81. Which is primarily responsible for low-level divergence acting as a braking mechanism for a high?

Explanation

Friction is primarily responsible for low-level divergence acting as a braking mechanism for a high. Friction occurs when two surfaces come into contact and resist each other's motion. In the context of weather systems, when a high-pressure system moves over a surface with lower pressure, the air tends to flow from the high-pressure area to the low-pressure area. However, friction between the air and the surface slows down this movement, causing divergence or spreading out of the air. This divergence acts as a braking mechanism for the high-pressure system, preventing it from intensifying further.

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82. Pilot reported ceiling heights must be converted from height above

Explanation

The pilot needs to convert the ceiling heights from mean sea level to height above ground level. This means that the reported heights need to be adjusted to reflect the distance above the ground rather than the distance above mean sea level. This is important for accurate navigation and communication with air traffic control, as the pilot needs to know the height of obstacles and terrain relative to their current altitude above the ground.

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83. As air converges at the surface and toward the center of a layer, there will be horizontal

Explanation

When air converges at the surface and toward the center of a layer, it experiences a decrease in horizontal area, leading to contraction. At the same time, there is an upward movement of air due to this convergence, causing vertical expansion. Therefore, the correct answer is "contraction and vertical expansion."

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84. You are preparing to use a convective cloud height table to determine the heights of clouds. To do this properly, you must first determine the

Explanation

To properly determine the heights of clouds using a convective cloud height table, it is necessary to know the dew-point temperature and free-air temperature. The dew-point temperature is the temperature at which air becomes saturated and condensation begins. It is a measure of the amount of moisture in the air. The free-air temperature, on the other hand, is the temperature of the surrounding air. By knowing these two temperatures, one can accurately determine the height of clouds using the convective cloud height table.

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85. The temperature an air parcel would have if it were cooled adiabatically to saturation at constant pressure by evaporation of water into it is called

Explanation

The wet bulb temperature refers to the temperature that an air parcel would have if it were cooled adiabatically to saturation at constant pressure by evaporation of water into it. This is different from the dry bulb temperature, which is the temperature of the air measured with a regular thermometer. The wet bulb temperature takes into account the cooling effect of evaporation and is often used to determine the level of humidity in the air.

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86. A warm barotropic high is a type of pressure system that

Explanation

A warm barotropic high is a type of pressure system that has great vertical extent, meaning it extends over a large range of altitudes. It is usually found over water areas, which suggests that it forms over bodies of water rather than over land. This could be due to the fact that water has a higher heat capacity than land, allowing for the formation of a more extensive and stable high pressure system.

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87. Which region of the United States favors the development of frontal occlusions?

Explanation

The correct answer is North. The region of the United States that favors the development of frontal occlusions is the North. This is because frontal occlusions occur when a warm air mass collides with a cold air mass, and the North region of the United States experiences more frequent clashes between warm and cold air masses due to its geographical location. These clashes lead to the formation of frontal occlusions, which can result in various weather phenomena such as rain, snow, and storms.

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88. A stable air mass that formed over land in the Arctic has now moved over the ocean's warmer surface.  You would classify this air mass as

Explanation

Located on page 1-51

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89. Explain why the sky is blue.

Explanation

Located on page 1-9

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90. The designated runway visual range (RVR) runway is

Explanation

The designated runway visual range (RVR) runway refers to any runway that has been instrumented with a transmissometer. A transmissometer is a device that measures the visibility on the runway by transmitting a light beam and measuring the amount of light that is able to pass through the atmosphere. By instrumenting the runway with a transmissometer, the RVR can be accurately determined, which is crucial information for pilots during takeoff, landing, and taxiing operations. Therefore, the correct answer is any runway that has been instrumented with a transmissometer.

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91. A cyclone that develops on a polar front, does not intensify significantly, and never occludes is called

Explanation

A cyclone that develops on a polar front refers to a low-pressure system that forms along the boundary between polar air and warmer air. If this cyclone does not intensify significantly, it means that it does not strengthen or grow in size. Additionally, if it never occludes, it means that the warm and cold fronts associated with the cyclone do not merge and cut off the warm sector. Therefore, this type of cyclone can be described as stable, as it remains relatively weak and does not undergo significant changes or occlusion.

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92. Which heat transfer process vertically transports the atmospheric properties of heat and moisture and is a more efficient method of heat transfer than by molecular motion?

Explanation

Located on page 1-48

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93. Which factors act as air mass modifiers?

Explanation

Located on page 1-54

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94. Using average surface frontal slopes, how far behind of the surface cold front is the jet stream located?

Explanation

Located on page 1-39

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95. Using average surface frontal slopes, how far ahead of the surface warm front is the jet stream located?

Explanation

Located on page 1-39

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96. Air mass stability characteristics often depend on the temperature difference between the

Explanation

Located on page 1-51

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97. What is the reference level for all pressure values?

Explanation

Sea-level pressure is the reference level for all pressure values. It is the atmospheric pressure at sea level, adjusted to the mean sea level. This reference level is used to compare and standardize pressure measurements taken at different altitudes. Station pressure refers to the atmospheric pressure at a specific location, altimeter setting is the atmospheric pressure adjusted for the altitude of an aircraft, and corrected aneroid reading is a term not commonly used in reference to pressure. Therefore, sea-level pressure is the correct answer as it provides a consistent baseline for pressure measurements.

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98. Which air mass involves most of the wintertime storms for the North American Pacific coast?

Explanation

Located on page 1-59

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99. The atmosphere properties that can be a measure of the strength of a frontal system are thickness gradient, 

Explanation

The correct answer is temperature gradient, lapse rate, turbulence, and wind shear. These atmospheric properties can be used to measure the strength of a frontal system. Temperature gradient refers to the change in temperature over a given distance, which can indicate the intensity of the front. Lapse rate is the rate at which temperature changes with altitude, and a steep lapse rate can indicate a strong front. Turbulence is the chaotic movement of air, which can be heightened in the presence of a front. Wind shear refers to the change in wind speed or direction over a short distance, and strong wind shear can indicate a powerful front.

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100. The cold conveyor belt originates in the low levels that are located

Explanation

The cold conveyor belt originates east of a low center and flows westward. This is because in a low-pressure system, air circulates counterclockwise. The cold conveyor belt is part of this counterclockwise circulation and is located to the east of the low center. It brings cold air from higher latitudes and transports it towards the west, contributing to the formation of clouds and precipitation on the eastern side of the low-pressure system.

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101. A warm frontal occlusion occurs when the cool air

Explanation

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102. For a runway visual range (RVR) report of R22/1000V1600FT, what is the visual range that a pilot can expect to see down the runway?

Explanation

The RVR report of R22/1000V1600FT indicates that the runway visual range is 1,600 meters. The "R22" indicates that the visual range is 1,600 meters, and the "1000V1600FT" indicates that the visual range can vary between 1,000 feet and 1,600 feet. Therefore, the pilot can expect to see a visual range of 1,600 meters down the runway.

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103. What pressure value is the basis for determining all other pressure values?

Explanation

Station pressure is the basis for determining all other pressure values because it represents the actual atmospheric pressure at a specific location. Altimeter setting is a corrected value of station pressure, sea-level pressure is the station pressure adjusted to sea-level, and corrected aneroid reading is a measurement taken by an aneroid barometer that has been calibrated to account for errors. Therefore, station pressure is the most fundamental and accurate measurement of pressure.

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104. An intense cyclogenesis normally occurs in troughs with a

Explanation

An intense cyclogenesis refers to the rapid development of a cyclone or low-pressure system. In this case, the correct answer suggests that intense cyclogenesis occurs in troughs with a negative tilt that is oriented northwest/southeast. A negative tilt means that the trough is tilted from southwest to northeast, which allows for the convergence of warm and cold air masses. This convergence leads to the formation of a strong low-pressure system and the intensification of the cyclone. The northwest/southeast orientation indicates the direction of the tilt, which further enhances the conditions for cyclogenesis.

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105. In relation to the jet core, the greatest horizontal wind shear is usually located

Explanation

Located on page 1-32

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106. You would classify precipitation as intermittent if it

Explanation

Intermittent precipitation refers to precipitation that stops and starts at least once within the preceding hour. This means that there is a break in the precipitation, followed by a resumption of precipitation within the hour. This classification is based on the frequency of the start and stop of precipitation within a specific time frame.

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107. Which high cloud can occasionally be so transparent that the only indication of its presence is a halo phenomenon?

Explanation

High cloud H7, also known as cirrostratus clouds, can occasionally be so transparent that the only indication of its presence is a halo phenomenon. Cirrostratus clouds are thin and wispy clouds that form at high altitudes, usually above 20,000 feet. They are composed of ice crystals and can create a halo effect around the sun or moon due to the refraction and reflection of light. This halo phenomenon is a result of the cloud's transparency and the interaction of light with the ice crystals in the cloud.

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108. With an inactive cold front, the net flow is

Explanation

An inactive cold front refers to a situation where the cold air mass is not advancing towards the warm air mass. In this case, there is no significant vertical motion or uplift of air along the front. Therefore, the net flow of air is generally upward, as there is no downward motion or sinking of air.

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109. The earth's atmosphere receives the most heating through the process of

Explanation

Located on page 1-5

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110. The primary difference between stratus and altostratus clouds is

Explanation

The primary difference between stratus and altostratus clouds is the composition of the clouds. Stratus clouds are low-level clouds that are uniform and layered, often covering the entire sky. They are composed of water droplets and sometimes ice crystals. On the other hand, altostratus clouds are mid-level clouds that are also layered but usually thicker and darker than stratus clouds. They are composed of both water droplets and ice crystals, and often indicate the approach of a warm front or a storm system. Therefore, the composition of the clouds is what sets stratus and altostratus clouds apart from each other.

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111. Cirrus clouds in the form of an anvil are classified as

Explanation

Cirrus clouds in the form of an anvil are classified as H3. This classification is based on the shape and appearance of the cloud. An anvil-shaped cirrus cloud typically indicates the presence of a strong thunderstorm or severe weather conditions. The H3 classification helps meteorologists identify and categorize different types of clouds based on their characteristics.

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112. The rate that an air mass modifies depends on the

Explanation

Located on page 1-61

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113. In comparison to an active cold front, an inactive cold front is characterized by a relatively

Explanation

An inactive cold front is characterized by a steeper slope, a narrow weather pattern, and is called a katafront. This means that the boundary between the cold air mass and the warm air mass is more pronounced and has a sharper angle. The weather associated with an inactive cold front is generally less active and may not produce as much precipitation as an active cold front. The narrow weather pattern indicates that the front is more focused and concentrated, affecting a smaller area. The term "katafront" is used to describe this type of front.

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114. What causes the subtropical jet (STJ) to recurve?

Explanation

Located on page 1-35

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115. Low cloud bases range from

Explanation

Low cloud bases refer to the height at which clouds are formed and are typically measured from the surface of the Earth. In this case, the correct answer states that low cloud bases range from near the surface to 6,500 feet above ground level. This means that the clouds are formed relatively close to the ground and can extend up to a height of 6,500 feet above the ground.

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116. A corona is often present at night with

Explanation

Altocumulus clouds often form a corona at night. A corona is a ring of light that surrounds the sun or the moon and is caused by the diffraction, or bending, of light around water droplets or ice crystals in the atmosphere. Altocumulus clouds are mid-level clouds that consist of water droplets and are often associated with fair weather. Their presence at night can create the conditions necessary for a corona to form, making them the correct answer.

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117. You are evaluating a jet maximum in straight line flow. To do this properly, you would locate the maximum area of convergence at the

Explanation

In order to evaluate a jet maximum in straight line flow, it is important to locate the maximum area of convergence. The left rear quadrant is the correct answer because it is the area where the flow is converging the most. This means that the velocity of the fluid is increasing in this region, indicating the presence of a jet maximum. The left front, right rear, and right front quadrants do not experience as much convergence, so they are not the correct locations for the maximum area of convergence.

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118. Wein's law states that

Explanation

located on page 1-45

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119. To achieve geostrophic windflow, there must be a balance between

Explanation

Located on page 1-18

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120. How would you classify middle clouds that can lower to within several hundred feet of the surface?

Explanation

Middle clouds that can lower to within several hundred feet of the surface are classified as M2.

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121. The balance of forces needed for gradient cyclonic circulation is pressure gradient

Explanation

Located on page of 1-21

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122. In the baroclinic instability process,

Explanation

In the baroclinic instability process, potential energy is transferred to the major short wave by thermal advection. This means that the transfer of potential energy to the short wave is facilitated by the movement of heat through the atmosphere. As the warm and cold air masses interact, the potential energy in the system is converted into kinetic energy, leading to the formation of the major short wave. The thermal advection plays a crucial role in this energy transfer process.

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123. In the summer, the continental highs

Explanation

Located on page 1-61

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124. The balance of forces needed for gradient anticyclonic circulation are presure gradient

Explanation

Located on page 1-20

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Which orographic cloud resembles an almond or a fish?
"Clouds or obscuring phenomena that have bases at the same approximate...
A decrease of mass in a column of air will cause the surface pressure...
How do you report prevailing visibility at US stations and overseas...
To properly report the visibility for more than one sector, you would...
What is the intensity of snow which restricts visibility to less than...
What air mass forms over land only during the summer?
"Jet fingers"
An increase of mass in a column of air will cause the surface pressure...
When the central pressure of an anticyclone is rising, you can infer...
Unstable waves are classified as
The distinguishing feature of any tornadic activity is
The best way to distinguish stratocumulus from altocumulus clouds is...
In the life cycle of a low, the wave will reach its maximum intensity...
What causes a surface high to build during the self-development...
A high-pressure system undergoes anticyclolysis when the clockwise...
Above 13 miles, the radiation from the sun breaks down the oxygen in...
A thunderstorm officially ends
Which high cloud classification is also referred to as a mackerel sky?
It is winter. A cPk air mass is moving over the great lakes. In this...
The three circulation cells in the three-cell circulation theory are
In a warm frontal occlusion, the coldest air is found
The simplest method for locating the 500 millibar frontal zone is to
If you throw a ball towards a stationary target from the window...
The damper effect is comprised of upper-level
A low-pressure system undergoing cyclogenesis is said to be
What type of precipitation might you observe with clear skies?
Precipitation is reported to the nearest
What air mass calssification signifies an unstable, maritime tropical...
What air mass classification signifies a stable, continental polar air...
Continental tropical air masses are usually associated with
When an inactive front passes your station, the dew points will
Centrifugal force will increase when there is a decrease in
For observing purposes, five hydrometers are considered to be...
How many degrees centigrade does the temperature decrease per 1,000...
With the passage of a cold front in the Northern Hemisphere, the...
What factors must a region possess in order to facilitate air mass...
The driving mechanism that is mainly responsible for the...
In a cold occlusion, the coldest air is found
In relation to the jet core, the greatest vertical wind shear is...
The  most desirable night-visibility markers are
The three main forms of precipitation are liquid,
Which type of obstruction to vision is classified as a lithometer?
Which is a calculated sea-level pressure in inches of mercury?
Wind observing equipment is oriented to
Which force is the "equal and opposite reaction" to the...
What color balloon would you use to determine the ceiling heights of...
The jet core that is located between the midlatitude and the tropical...
Anticyclogenesis typically occurs at, and just downstream from,...
A sudden increase of wind speed of at least 16 knots and a sustained...
Surface pressure changes are largely controlled by
What causes the surface low to deepen during the self-development...
Advection transfers temperature
The average slope of a cold front is
Which heat transfer process involves the transfer of energy by...
The areas of low pressure that correspond to the belt of low pressure...
The primary cause of surface pressure changes for a dynamic low is net
How many stages are there in the life cycle of a low?
The width of the jet stream core is approximately equal to the
What will the jet stream usually do when a cold, moving, polar high...
Which is true of water vapor in the atmosphere?
Horizontal divergence within an air mass will
Frontogenesis requires two adjacent air masses with
Which low cloud type and classification is identified by the presence...
Blowing spray is reported only at sea stations near large bodies of...
A low dissipates after proceeding through its entire life cycle which...
The weather characteristics of a particular month in a given locality...
Converging contours downstream of the jet stream will cause the jet to
Coriolis force is created by
After warm air with an unstable wave is pushed aloft and cuts off from...
Which process is most responsible for the slow formation of air masses...
A thunderstorm is present and occurring at your station. In addition,...
When only high and middle clouds are associated with a warm front, the
The force that is responsible for starting the horizontal movement of...
The frontolytic processes are most effective
When using Petterssen's rule, the factors needed for cyclogenesis are...
The best sources for identifying a frontal inversion are the
The two atmospheric gases most responsible for the absorption of...
The stratosphere is characterized by
Aloft, during the baroclinic instability process, the thermal wave and...
Which is primarily responsible for low-level divergence acting as a...
Pilot reported ceiling heights must be converted from height...
As air converges at the surface and toward the center of a layer,...
You are preparing to use a convective cloud height table to determine...
The temperature an air parcel would have if it were cooled...
A warm barotropic high is a type of pressure system that
Which region of the United States favors the development of frontal...
A stable air mass that formed over land in the Arctic has now moved...
Explain why the sky is blue.
The designated runway visual range (RVR) runway is
A cyclone that develops on a polar front, does not intensify...
Which heat transfer process vertically transports the atmospheric...
Which factors act as air mass modifiers?
Using average surface frontal slopes, how far behind of the...
Using average surface frontal slopes, how far ahead of the surface...
Air mass stability characteristics often depend on the temperature...
What is the reference level for all pressure values?
Which air mass involves most of the wintertime storms for the North...
The atmosphere properties that can be a measure of the strength of a...
The cold conveyor belt originates in the low levels that are located
A warm frontal occlusion occurs when the cool air
For a runway visual range (RVR) report of R22/1000V1600FT, what is the...
What pressure value is the basis for determining all other pressure...
An intense cyclogenesis normally occurs in troughs with a
In relation to the jet core, the greatest horizontal wind shear is...
You would classify precipitation as intermittent if it
Which high cloud can occasionally be so transparent that the only...
With an inactive cold front, the net flow is
The earth's atmosphere receives the most heating through the...
The primary difference between stratus and altostratus clouds is
Cirrus clouds in the form of an anvil are classified as
The rate that an air mass modifies depends on the
In comparison to an active cold front, an inactive cold front is...
What causes the subtropical jet (STJ) to recurve?
Low cloud bases range from
A corona is often present at night with
You are evaluating a jet maximum in straight line flow. To do this...
Wein's law states that
To achieve geostrophic windflow, there must be a balance between
How would you classify middle clouds that can lower to within several...
The balance of forces needed for gradient cyclonic circulation is...
In the baroclinic instability process,
In the summer, the continental highs
The balance of forces needed for gradient anticyclonic circulation are...
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