1.
What are the three states of matter?
Correct Answer
A. Solid, Liquid, Gaseous
Explanation
The three states of matter are solid, liquid, and gaseous. These states are determined by the arrangement and movement of particles. In a solid, particles are tightly packed and have a fixed shape and volume. In a liquid, particles are close together but can move around, giving it a definite volume but no fixed shape. In a gaseous state, particles are spread out and move freely, resulting in no fixed shape or volume.
2.
What is happening when a solid becomes a liquid?
Correct Answer
B. Fusion
Explanation
When a solid becomes a liquid, it undergoes a process called fusion. Fusion is the phase transition in which a substance changes from a solid state to a liquid state. This occurs when the temperature of the solid is raised above its melting point, causing the particles within the solid to gain enough energy to break free from their fixed positions and move more freely, resulting in a liquid state.
3.
What two effects cause differences in saturation vapor pressure (es) in terms of CCN growth?
Correct Answer
C. Solute and Curvature
Explanation
The differences in saturation vapor pressure (es) in terms of CCN growth are caused by the solute and curvature effects. The solute effect occurs when CCNs absorb water molecules and the dissolved substances in the CCNs lower the saturation vapor pressure. The curvature effect occurs due to the curvature of the CCN surface, which causes a higher saturation vapor pressure compared to a flat surface. These two effects contribute to the differences in es during CCN growth.
4.
What is a general tool for forecasting clouds that is derived from decades of observational data
and is a time-proven method?
Correct Answer
A. Climatology
Explanation
Climatology is a general tool for forecasting clouds that is derived from decades of observational data and is a time-proven method. It involves the study of long-term weather patterns and trends, allowing forecasters to make predictions based on historical data. By analyzing past weather conditions and patterns, climatology can provide valuable insights into cloud formation and behavior, helping to forecast cloud cover, precipitation, and other related weather phenomena. This makes climatology a reliable and effective tool for cloud forecasting.
5.
What general tool for forecasting clouds is generated from model data and provides guidance on
relative cloud amount and height range out to 48 hours?
Correct Answer
D. Forecast relative humidity values
Explanation
Forecast relative humidity values can be used as a general tool for forecasting clouds. Cloud formation is closely related to humidity levels in the atmosphere. Higher humidity levels indicate a greater likelihood of cloud formation. By forecasting relative humidity values, meteorologists can estimate the amount and height range of clouds that are likely to form in the next 48 hours. This information is generated from model data and provides guidance for cloud forecasting.
6.
What general tool for cloud forecasting is being used when you simply advect clouds from their
current location downstream?
Correct Answer
B. Extrapolation
Explanation
Extrapolation is the correct answer because it refers to the process of estimating or predicting future values based on the existing data or trends. In the context of cloud forecasting, when clouds are advected or moved downstream from their current location, it implies that their future position is being predicted based on their current movement. This process involves extrapolation, where the existing cloud movement data is used to forecast their future positions.
7.
Which general tool for forecasting clouds should NOT be used without other supporting
products?
Correct Answer
C. Weather Radar
Explanation
Weather radar is a general tool for forecasting clouds, but it should not be used without other supporting products. Weather radar provides information about precipitation and the movement of clouds, but it does not provide detailed information about cloud types, heights, or other important factors that can be obtained from other products such as meteograms, METARs, and PIREPs. Therefore, relying solely on weather radar for cloud forecasting may result in incomplete or inaccurate predictions.
8.
What is the main difference and added consideration when forecasting cumuliform clouds versus
stratiform clouds?
Correct Answer
A. AtmospHeric Stability
Explanation
When forecasting cumuliform clouds, the main difference and added consideration compared to stratiform clouds is atmospheric stability. Cumuliform clouds are associated with unstable atmospheric conditions, which means that there is a lot of vertical movement and turbulence in the atmosphere. This instability can lead to the formation of towering cumulonimbus clouds and potentially severe weather such as thunderstorms. On the other hand, stratiform clouds are associated with stable atmospheric conditions, where the air is more uniform and there is less vertical movement. This difference in atmospheric stability is an important factor to consider when forecasting these two types of clouds.
9.
At what level do clouds form when mechanical lift is the predominant factor?
Correct Answer
A. LCL
Explanation
The LCL (Lifting Condensation Level) is the level at which clouds form when mechanical lift is the predominant factor. Mechanical lift refers to the lifting of air caused by physical processes such as topography or frontal systems. When air is lifted, it cools and reaches its dew point, resulting in the formation of clouds. Therefore, the LCL represents the altitude at which this lifting and cloud formation occurs in the atmosphere.
10.
Would precipitation occcur with a wew point spread of 4ï‚°C at 850 and 700mb?
Correct Answer
B. No
Explanation
Precipitation occurs when the air is saturated with moisture. The dew point spread is the difference between the temperature and the dew point. A dew point spread of 4ï‚°C indicates that the air is not very moist. Therefore, with a dew point spread of 4ï‚°C at 850 and 700mb, precipitation is unlikely to occur.
11.
Generally, what front is connected with the snow or rain zone?
Correct Answer
D. Polar
Explanation
The correct answer is Polar. The polar front is connected with the snow or rain zone. The polar front is a boundary between polar air masses and warmer air masses, typically found in the mid-latitudes. This front is often associated with the formation of low-pressure systems and the development of precipitation, including snow and rain.
12.
With a flat, fast westerly flow aloft, in which direction does the snow or rain zone spread?
Correct Answer
C. Eastward
Explanation
With a flat, fast westerly flow aloft, the snow or rain zone would spread eastward. This is because the westerly flow would push the precipitation system from west to east, causing it to spread in an eastward direction.
13.
What is the most common type of fog in the Northern Hemisphere?
Correct Answer
B. Radiation Fog
Explanation
Radiation fog is the most common type of fog in the Northern Hemisphere. This type of fog forms during the night when the ground radiates heat, causing the air near the surface to cool. As the air cools, it reaches its dew point and condenses into fog. Radiation fog is typically shallow and forms in low-lying areas such as valleys and basins. It is often associated with calm and clear nights, and dissipates once the sun rises and the ground begins to warm up.
14.
What type of fog forms in higher elevations and builds downward?
Correct Answer
B. Upslope Fog
Explanation
Upslope fog forms in higher elevations and builds downward. As moist air is forced up a slope or mountain, it cools and condenses into fog. This type of fog is commonly observed in mountainous regions where air is forced to rise over the terrain. As the air ascends, it cools and reaches its dew point, leading to the formation of fog. This fog then descends down the slope, often resulting in reduced visibility and damp conditions in valleys and lower elevations.
15.
What type of fog is usually limited to areas near human habitation?
Correct Answer
D. Ice Fog
Explanation
Ice fog is a type of fog that occurs in very cold temperatures, typically below -35°C. It is characterized by the presence of tiny ice crystals suspended in the air, which can create a white or grayish foggy appearance. Unlike other types of fog, ice fog is usually limited to areas near human habitation, where sources of heat and moisture contribute to its formation. The cold temperatures and high humidity in these areas create the perfect conditions for ice fog to occur, making it a common phenomenon in urban environments.
16.
This restriction develops in layers in a stable atmosphere usually of fairly large depth. The
visibility is usually between three and six miles. To predict this restriction, you must locate a
source of pollution and predict the stagnation of an air mass in your area.
Correct Answer
D. Haze
Explanation
Haze is the correct answer because the given information suggests that the restriction in visibility is caused by a stable atmosphere and the presence of pollution. Haze is a type of atmospheric pollution characterized by the presence of fine particles or pollutants in the air, which can reduce visibility and create a hazy appearance. It is often caused by industrial emissions, vehicle exhaust, or other sources of pollution. Therefore, haze is the most likely explanation for the restriction in visibility described in the question.
17.
What is the intensity of snow showers occurring at you station with a prevailing visibility of fiveeighths
of a mile?
Correct Answer
A. Light
Explanation
The intensity of snow showers occurring at the station with a prevailing visibility of fiveeighths of a mile is considered light. This means that the snowfall is not very heavy or intense, but rather gentle and not causing significant disruptions or hazards.
18.
Which general tool for forecasting winds can provide information on surface frictional effects?
Correct Answer
C. TopograpHy
Explanation
Topography refers to the physical features of the Earth's surface, such as mountains, hills, and valleys. These features can significantly impact wind patterns and create variations in wind speed and direction. By studying the topography of a specific area, forecasters can better understand how surface frictional effects, caused by the interaction between the wind and the Earth's surface, will influence wind patterns. Therefore, topography is a useful tool for forecasting winds and providing information on surface frictional effects.
19.
Which general tool for forecasting winds are graphical in nature, based on the WRF model and
provide wind forecasts for three hour intervals?
Correct Answer
C. Meteogram
Explanation
Meteograms are graphical tools that provide wind forecasts based on the WRF model. They display wind speed and direction for three hour intervals, allowing users to easily visualize and interpret the forecasted wind patterns. This makes meteograms a useful tool for forecasting winds in various applications such as aviation, agriculture, and outdoor activities.
20.
What would the approximate low-level wind speed be if open-cell cumulus in the shape of an
elongated doughnut was present?
Correct Answer
C. 11-20kts
Explanation
If open-cell cumulus in the shape of an elongated doughnut is present, the approximate low-level wind speed would be around 11-20 knots.
21.
What is the nocturnal wind that flows into valleys?
Correct Answer
A. Mountain Breeze
Explanation
A mountain breeze is a type of wind that flows from higher elevations down into valleys during the night. As the air cools at higher altitudes, it becomes denser and flows downhill, creating a breeze that is felt in the valleys. This phenomenon occurs because the mountains cool faster than the surrounding air, causing the air to flow down the slopes and into the valleys. Therefore, the correct answer is Mountain Breeze.
22.
Which two winds belong to the category of Fall Winds?
Correct Answer
D. Mistral and Bora
Explanation
The correct answer is Mistral and Bora. Mistral is a strong, cold wind that blows from the northwest in southern France, while Bora is a cold and dry wind that blows from the northeast in the Adriatic Sea region. Both of these winds are associated with the fall season and are known for their strength and impact on the local weather conditions.
23.
Cap, rotor, and lenticular clouds are characteristic of which forced-circulation wind?
Correct Answer
A. Foehn Winds
Explanation
Cap, rotor, and lenticular clouds are characteristic of Foehn Winds. Foehn Winds are warm, dry winds that occur when air is forced over a mountain range and descends down the leeward side. As the air descends, it warms adiabatically, causing moisture to evaporate and form these unique cloud formations. These winds are commonly found in mountainous regions and can have significant effects on local weather patterns.
24.
What tool provides a summary of monthly and annual climatic data for a station?
Correct Answer
C. OCDS
Explanation
OCDS stands for the Online Climatic Data System, which is a tool that provides a summary of monthly and annual climatic data for a station. This tool allows users to access and analyze climatic data for specific locations, helping them understand the climate patterns and trends over time. It is a valuable resource for researchers, meteorologists, and anyone interested in studying or monitoring climate conditions.
25.
How does a stable lapse rate affect heating?
Correct Answer
B. Heating occurs more rapidly
Explanation
A stable lapse rate refers to a situation where the temperature decreases at a slower rate with increasing altitude. In this case, heating occurs more rapidly because the air near the surface is warmer than the air higher up. As a result, the warm air near the surface rises more quickly, leading to faster heating of the atmosphere.
26.
How do strong winds affect heating?
Correct Answer
C. There is less heating due to greater mixing.
Explanation
Strong winds affect heating by causing greater mixing of air. When there is greater mixing, the warm air near the surface gets dispersed and replaced by cooler air from higher altitudes. As a result, the overall temperature decreases, leading to less heating.
27.
What is a cold wave?
Correct Answer
B. A cold wave in the U S is a net decrease of 20 F or more in 24 hours with the temperature falling below a preset minimum.
Explanation
A cold wave in the U.S. is defined as a significant drop in temperature, specifically a net decrease of 20°F or more, occurring within a span of 24 hours, and with the temperature falling below a predetermined minimum threshold. This means that during a cold wave, there is a rapid and substantial decrease in temperature over a 24-hour period, resulting in extremely cold conditions that fall below the preset minimum temperature.
28.
What is the D-value?
Correct Answer
D. D = true altitude - standard altitude.
Explanation
The D-value is calculated by subtracting the standard altitude from the true altitude. This means that the D-value represents the difference between the actual altitude of an aircraft and the standard or reference altitude. It is used in aviation to determine the vertical separation between aircraft and to ensure safe and efficient air traffic control.
29.
What is density altitude?
Correct Answer
C. The altitude that a given density is found in the standard atmospHere
Explanation
Density altitude is a term used in aviation to describe the altitude at which a certain air density is found in the standard atmosphere. It is calculated by taking into account the temperature and pressure at a specific location and comparing it to the standard atmospheric conditions. This information is important for pilots as it affects aircraft performance, such as engine power and lift. By knowing the density altitude, pilots can make adjustments to their flight plans and ensure safe operations.
30.
Which term defines a change in state from a solid to a gas?
Correct Answer
C. Sublimation.
Explanation
Sublimation is the term that defines a change in state from a solid to a gas. This process occurs when a solid directly transitions into a gaseous state without passing through the liquid state. Examples of sublimation include dry ice (solid carbon dioxide) turning into carbon dioxide gas and mothballs (solid naphthalene) gradually vaporizing into the air.
31.
What changes of state absorb heat from the surrounding environment?
Correct Answer
A. Vaporization, fusion, and sublimation.
Explanation
Vaporization, fusion, and sublimation are changes of state that absorb heat from the surrounding environment. Vaporization occurs when a substance changes from a liquid to a gas, fusion is the process of a substance changing from a solid to a liquid, and sublimation is when a substance changes directly from a solid to a gas. In all of these processes, heat is absorbed from the surroundings to provide the energy needed for the phase change to occur.
32.
What is the most efficient method of cloud droplet growth?
Correct Answer
C. Collision and coalescence.
Explanation
The most efficient method of cloud droplet growth is through collision and coalescence. When cloud droplets collide, they combine and form larger droplets in a process called coalescence. This leads to the growth of cloud droplets and eventually the formation of raindrops. Condensation alone is not as efficient in increasing the size of cloud droplets, and collision and evaporation would result in a decrease in droplet size rather than growth. Therefore, collision and coalescence is the correct answer for the most efficient method of cloud droplet growth.
33.
What term is used to define the process where the outer edge of the cloud mixes with air
outside of the cloud?
Correct Answer
D. Dry-air entrainment.
Explanation
Dry-air entrainment is the term used to define the process where the outer edge of the cloud mixes with air outside of the cloud. This occurs when drier air from the surrounding environment is drawn into the cloud, causing the cloud to mix and interact with this dry air. It can have significant effects on the cloud's structure and behavior, as the dry air can lead to evaporation of cloud droplets and changes in cloud dynamics.
34.
Which cloud forecasting tool is biased towards climatology (average conditions), and may
not be accurate during abnormal conditions?
Correct Answer
A. Model output statistics.
Explanation
Model output statistics (MOS) is a cloud forecasting tool that is biased towards climatology, meaning it relies on average conditions to make predictions. However, during abnormal conditions, such as extreme weather events, MOS may not accurately forecast cloud conditions. This is because it does not take into account the specific circumstances that deviate from the average. Therefore, MOS may not be the most reliable tool for forecasting cloud conditions during abnormal situations.
35.
You would not expect stratus clouds to form when:
Correct Answer
A. The curvature is anticyclonic.
Explanation
When the curvature is anticyclonic, it means that the air is sinking and diverging. Stratus clouds typically form when warm, moist air is lifted and condensed. In anticyclonic conditions, the sinking air prevents the formation of clouds as it inhibits the upward movement of air. Therefore, it is not expected for stratus clouds to form in this situation.
36.
A very narrow band of clouds associated with a cold front may indicate the
Correct Answer
B. 700mb contours are perpendicular to the surface cold front.
37.
The type and intensity of precipitation observed at the earth’s surface is related to the
thickness of the cloud aloft, and particularly to the
Correct Answer
D. Temperatures in the upper part of the cloud.
Explanation
The type and intensity of precipitation observed at the earth's surface is related to the temperatures in the upper part of the cloud. This is because the temperature in the upper part of the cloud determines whether the moisture in the cloud will freeze or remain in liquid form. If the temperature is below freezing, the moisture will freeze and form ice crystals or snowflakes, resulting in precipitation such as snow. If the temperature is above freezing, the moisture will remain in liquid form, resulting in precipitation such as rain. Therefore, the temperatures in the upper part of the cloud play a crucial role in determining the type of precipitation that will occur.
38.
With a quasistationary front in the southern United States under a broad west or southwest
flow aloft and a weak surface low, the snow rain zone becomes
Correct Answer
A. Elongated in the direction of the upper-level current with precipitation rates stretching over long
periods.
Explanation
The correct answer is "elongated in the direction of the upper-level current with precipitation rates stretching over long periods." This means that the snow rain zone is stretched out in the same direction as the upper-level current, and the precipitation rates are sustained for a longer duration. This suggests that the weather system is characterized by a slow-moving front and a weak surface low, resulting in prolonged and widespread precipitation over the region.
39.
Which condition increases the probability of fog formation?
Correct Answer
B. Advecting a warm, moist air mass over a cold surface.
Explanation
When a warm, moist air mass is advected (transported) over a cold surface, the temperature difference between the air mass and the surface causes the air to cool rapidly. This rapid cooling leads to condensation of water vapor in the air, forming fog. Therefore, advecting a warm, moist air mass over a cold surface increases the probability of fog formation.
40.
What type of air mass causes a persistent type of continental high-inversion fog to occur in
valleys?
Correct Answer
B. Maritime polar air.
Explanation
Maritime polar air masses are characterized by cool and moist air. When this air mass moves over a valley, it can become trapped due to the surrounding mountains or hills, creating a temperature inversion. This inversion prevents the fog from dissipating and leads to the formation of persistent continental high-inversion fog in valleys.
41.
Which visibility restriction is the most localized?
Correct Answer
D. Smoke.
Explanation
Smoke is the most localized visibility restriction because it tends to stay close to its source and does not disperse easily. Unlike haze, which can cover large areas and be present even in the absence of a specific source, smoke is usually emitted from a specific location such as a fire or industrial chimney. Wind-blown particles and precipitation can also reduce visibility, but they are not as localized as smoke since they can be carried over longer distances by the wind or spread over a wider area.
42.
What would the estimated low-level wind speed be, in knots, from satellite imagery
displaying arc-shaped open-cell cumulus clouds?
Correct Answer
A. 21 to 30kts
Explanation
Arc-shaped open-cell cumulus clouds are typically associated with convective activity and instability in the atmosphere. These types of clouds often indicate strong updrafts and downdrafts, which can result in higher wind speeds at lower levels. Therefore, it is reasonable to estimate that the low-level wind speed would be in the range of 21 to 30 knots.
43.
If no inversion is present, forecast the maximum surface wind gusts to be
Correct Answer
D. 80 percent of the 5,000-foot wind speed.
Explanation
In meteorology, wind speeds typically increase with height due to the decrease in surface friction. However, when an inversion is present, the temperature increases with height instead of decreasing. This temperature inversion acts as a cap, trapping the lower-level air and preventing it from mixing with the higher-level air. As a result, the wind speed does not increase as much with height in the presence of an inversion. Since the question states that no inversion is present, it can be inferred that the wind speed will increase with height. Therefore, the maximum surface wind gusts are forecasted to be 80 percent of the 5,000-foot wind speed.
44.
In forecasting frontal winds, the deepening or filling of a frontal trough:
Correct Answer
D. Increases or decreases the winds.
Explanation
The deepening or filling of a frontal trough can have varying effects on frontal winds. When a frontal trough deepens, it indicates an intensification of the temperature gradient, which can lead to stronger winds. On the other hand, when a frontal trough fills, it suggests a weakening of the temperature gradient and can result in weaker winds. Therefore, the deepening or filling of a frontal trough can cause both an increase or decrease in frontal winds, depending on the specific conditions.
45.
How many degrees are there between the freezing point and the boiling point on the Kelvin
temperature scale?
Correct Answer
A. 100
Explanation
There are 100 degrees between the freezing point and the boiling point on the Kelvin temperature scale.
46.
What type humidity is another expression of mixing ratio?
Correct Answer
B. Absolute.
Explanation
The question is asking for the type of humidity that is another expression of mixing ratio. The mixing ratio is the mass of water vapor present in the air compared to the mass of dry air. Absolute humidity, on the other hand, is the actual amount of water vapor present in the air regardless of the air's temperature or pressure. Therefore, absolute humidity is the correct answer as it directly relates to the mixing ratio.
47.
Which forecasting tool provides a summary of monthly and annual climatic data for a
station?
Correct Answer
A. Operational Climatic Data Summary (OCDS).
Explanation
The Operational Climatic Data Summary (OCDS) is the correct answer because it provides a summary of monthly and annual climatic data for a specific station. The other options, such as Modeled curves (MODCURVES), Weather research forecast (WRF) meteograms, and Model output statistics (MOS), do not specifically provide a summary of monthly and annual climatic data for a station.
48.
A heat wave over the Midwestern and eastern part of the United States develops when a
Correct Answer
A. Long-wave trough stagnates over the Rockies and a long-wave ridge lays over the east coast
Explanation
In this scenario, a heat wave develops over the Midwestern and eastern part of the United States when a long-wave trough stagnates over the Rockies and a long-wave ridge lays over the east coast. This creates a blocking high over the central United States, which prevents the movement of weather systems and traps hot air in the region. The stagnant trough and ridge pattern leads to prolonged periods of hot and dry weather, resulting in a heat wave.
49.
Which condition must exist for the development of a cold wave over the United States?
Correct Answer
B. Movement of a low eastward from the Continental Divide.
Explanation
A cold wave over the United States can develop when a low pressure system moves eastward from the Continental Divide. This movement of the low pressure system can bring cold air from the western parts of the country towards the eastern regions, leading to a drop in temperatures and the development of a cold wave. This movement of the low pressure system is a key factor in the development of cold waves over the United States.
50.
What values do you need to compute the pressure altitude?
Correct Answer
D. Field elevation and altimeter setting.
Explanation
To compute the pressure altitude, you need to know the field elevation, which is the elevation of the airport above sea level, and the altimeter setting, which is the current atmospheric pressure at sea level. The pressure altitude is then calculated by subtracting the altimeter setting from the field elevation. This is necessary because the altimeter measures pressure and not actual altitude, so adjusting for the current atmospheric pressure is essential to accurately determine the pressure altitude.