1W071 CDC Book 3
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Aside from the Air Force Operational Weather Squadrons (OWS), what agency produces discussions on model output?
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Joint Army Air Force Weather Information Network..
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Air Force Weather Agency..
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National Weather Service.
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Air Weather Service.
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The 1W071 CDC Book 3 quiz assesses knowledge in meteorology, focusing on operational weather forecasting. It covers model output discussions, severe weather analysis, and forecast verification processes, equipping learners with skills to analyze and predict severe weather conditions effectively.
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- 2.
What areas do Storm Prediction Center advisory charts outline?
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Areas of expected crosswinds.
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Areas of expected severe weather.
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Areas of frequent crosswind occurrence.
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Areas of frequent severe weather occurrence.
Correct Answer
A. Areas of expected severe weather.Explanation
Storm Prediction Center advisory charts outline areas of expected severe weather. These charts provide information on the likelihood and intensity of severe weather events such as tornadoes, thunderstorms, and hail. By outlining these areas, the charts help to alert and inform the public and emergency management agencies about the potential risks and impacts of severe weather.Rate this question:
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- 3.
What do you physically compare the 00-hour forecast with during the initialization step of the verification, initialization and verification (VIV) process?
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Analysis
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12-hour forecast.
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24-hour forecast.
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Previous 12-hour forecast.
Correct Answer
A. AnalysisExplanation
During the initialization step of the verification, initialization and verification (VIV) process, the 00-hour forecast is compared with the analysis data. The analysis data represents the current state of the atmosphere and is considered the most accurate representation of the weather conditions at that time. By comparing the 00-hour forecast with the analysis data, meteorologists can assess the accuracy and reliability of the forecast model and make any necessary adjustments before proceeding with the verification step.Rate this question:
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- 4.
What action is the final step of the verification, initialization and verification process?
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Verify the 00-hour forecast with your current analysis.
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Verify the 12-hour forecast with real-time data for the same time.
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Verify the previous 12-hour forecast with the current 12-hour forecast.
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Verify the previous 12-hour forecast against the current 00-hour forecast.
Correct Answer
A. Verify the 12-hour forecast with real-time data for the same time.Explanation
The final step of the verification, initialization, and verification process is to verify the 12-hour forecast with real-time data for the same time. This step ensures that the forecast made 12 hours ago aligns with the actual weather conditions observed at that time. By comparing the forecasted data with the real-time data, any discrepancies or inaccuracies can be identified and adjustments can be made if necessary. This verification step helps to improve the accuracy and reliability of the forecast model.Rate this question:
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- 5.
What initial conditions are models used based upon?
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Standard atmospheric conditions.
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Previously forecasted conditions.
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Current weather observations.
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Model of choice conditions.
Correct Answer
A. Current weather observations.Explanation
Models used in weather forecasting are based on current weather observations. These observations include data such as temperature, humidity, wind speed, and atmospheric pressure. By analyzing these current conditions, meteorologists can input the data into weather models to predict future weather patterns. This allows for more accurate and reliable forecasts. Standard atmospheric conditions, previously forecasted conditions, and model of choice conditions are not the basis for initial conditions in weather models.Rate this question:
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- 6.
What action is the goal of severe weather analysis?
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Identify the preconditions that allow storms to become severe.
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Identify the different types of severe thunderstorms.
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Determine the rear-flank downdraft wind direction.
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Determine the mid-level wind speed and direction.
Correct Answer
A. Identify the preconditions that allow storms to become severe.Explanation
The goal of severe weather analysis is to identify the preconditions that allow storms to become severe. This involves examining various factors such as atmospheric instability, moisture content, and wind patterns to determine the likelihood of severe weather development. By understanding these preconditions, meteorologists can better forecast and warn the public about potentially dangerous weather events.Rate this question:
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- 7.
How many minutes do single-cell storms typically last?
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20 to 30.
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20 to 40.
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30 to 45.
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30 to 60.
Correct Answer
A. 30 to 60.Explanation
Single-cell storms typically last between 30 to 60 minutes.Rate this question:
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- 8.
Which characteristic is not one of the single-cell thunderstorm?
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Storm motion equal to the mean wind in the lowest 5km to 7km.
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Weak vertical and horizontal wind shear.
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High winds and hail.
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Frequent tornadoes.
Correct Answer
A. Frequent tornadoes.Explanation
The characteristic that is not one of the single-cell thunderstorm is frequent tornadoes. Single-cell thunderstorms are typically short-lived and do not have strong enough updrafts to produce tornadoes. They are usually characterized by storm motion equal to the mean wind in the lowest 5km to 7km, weak vertical and horizontal wind shear, and high winds and hail. However, they are not known for frequently producing tornadoes.Rate this question:
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- 9.
Where do multi-cell storms typically regenerate?
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Along the gust front.
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The rear-flank downdraft.
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East of the westernmost cell.
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North of the 700mb wind maximum.
Correct Answer
A. Along the gust front.Explanation
Multi-cell storms typically regenerate along the gust front. The gust front is the leading edge of cool air that rushes out from a thunderstorm. As this cool air collides with warm, moist air, it can create new updrafts and initiate the formation of new thunderstorms. This process of regeneration along the gust front is common in multi-cell storms, which are composed of multiple individual cells that can develop and decay over time.Rate this question:
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- 10.
Which characteristic is not one of multi-cell thunderstorms?
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Weak directional shear in the lower levels.
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Straight-line or unidirectional profile.
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Large hail near downdraft centers.
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Short-duration tornadoes.
Correct Answer
A. Weak directional shear in the lower levels.Explanation
Multi-cell thunderstorms typically exhibit a strong directional shear in the lower levels, which means that the wind direction changes significantly with height. This helps to organize the storm and maintain its structure. Therefore, weak directional shear in the lower levels is not a characteristic of multi-cell thunderstorms.Rate this question:
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- 11.
Which thunderstorm is not a type of supercell thunderstorm?
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Classic.
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High precipitation.
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Low precipitation.
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Moderate precipitation.
Correct Answer
A. Moderate precipitation.Explanation
Moderate precipitation is not a type of supercell thunderstorm because supercell thunderstorms are characterized by intense updrafts and rotation, which lead to severe weather conditions such as large hail, strong winds, and tornadoes. Moderate precipitation refers to a level of rainfall that is not as heavy as high precipitation, but it does not indicate the presence of the specific characteristics of a supercell thunderstorm.Rate this question:
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- 12.
What size hail do classic supercell thunderstorms typically produce?
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Marble.
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Softball.
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Golf ball.
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Baseball.
Correct Answer
A. Golf ball.Explanation
Classic supercell thunderstorms typically produce hail the size of a golf ball.Rate this question:
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- 13.
Which type of supercell thunderstorm is most commonly found along the dry line of west Texas?
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Moderate-precipitation.
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High-precipitation.
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Low-precipitation.
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Classic.
Correct Answer
A. Low-precipitation.Explanation
Low-precipitation supercell thunderstorms are most commonly found along the dry line of west Texas. These types of storms have a lower amount of precipitation compared to other types of supercell thunderstorms. The dry line, which is a boundary between moist and dry air masses, creates an environment that is conducive for the formation of low-precipitation supercells. These storms typically have a higher potential for producing severe weather, such as large hail and strong winds, but have limited rainfall.Rate this question:
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- 14.
Which region is not a primary source for airmasses?
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Arctic.
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Tropical.
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Equatorial.
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Temperate.
Correct Answer
A. Temperate.Explanation
The temperate region is not a primary source for airmasses because it is located between the polar and tropical regions. Airmasses are formed in the polar and tropical regions due to the contrasting temperature and moisture conditions. The temperate region acts as a transition zone where airmasses from the polar and tropical regions mix and interact, but it is not a primary source for the formation of airmasses itself.Rate this question:
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- 15.
What letter or symbol is appended to the label of a modifying airmass that is cooler than the ground below?
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Plus symbol.
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Lower case c.
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Lower case k.
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Minus symbol.
Correct Answer
A. Lower case k.Explanation
When a modifying airmass is cooler than the ground below, it is labeled with a lowercase "k". This indicates that the airmass is colder than the surface it is moving over. The other options, such as the plus symbol, lowercase c, and minus symbol, do not specifically indicate that the airmass is cooler than the ground.Rate this question:
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- 16.
Where is the geographic area known as the "Great Plains" located?
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West of the Rocky Mountains.
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East of the Appalachian Mountains.
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Between the Mississippi River and the Rocky Mountains.
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Between the Appalachian Mountains and the Missouri River.
Correct Answer
A. Between the Mississippi River and the Rocky Mountains.Explanation
The geographic area known as the "Great Plains" is located between the Mississippi River and the Rocky Mountains. This region spans across several states in the central United States, including parts of Montana, Wyoming, North Dakota, South Dakota, Nebraska, Kansas, Colorado, Oklahoma, Texas, and New Mexico. It is characterized by vast, flat grasslands, with few trees and a semi-arid climate. The Great Plains is an important agricultural region, known for its production of wheat, corn, and other crops.Rate this question:
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- 17.
In what tornado-producing airmass do tornadoes most frequently occur in families, with paths that are commonly long and wide?
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Type II, Gulf Coast type.
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Type I, Great Plains type.
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Type III, Pacific Coast type.
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Type IV, Inverted “V” type.
Correct Answer
A. Type I, Great Plains type.Explanation
Tornadoes most frequently occur in families with long and wide paths in the Great Plains type of tornado-producing airmass. This region is known for its favorable atmospheric conditions for tornado formation, such as warm, moist air from the Gulf of Mexico colliding with cool, dry air from the Rocky Mountains. These conditions create strong wind shear and instability, which are essential for the development of tornadoes. The Great Plains region, stretching from Texas to North Dakota, is often referred to as "Tornado Alley" due to its high frequency of tornado occurrences.Rate this question:
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- 18.
What factor is evident above the inversion with a Type I airmass?
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Moisture increase.
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Rapid drying.
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Condensation.
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Turbulence.
Correct Answer
A. Rapid drying.Explanation
The factor that is evident above the inversion with a Type I airmass is rapid drying. This means that the air above the inversion is becoming drier at a fast rate.Rate this question:
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- 19.
Which type of airmass is tropical in origin and generally warm and moist?
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Type I Great Plains.
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Type II Gulf Coast.
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Type III Pacific Coast.
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Type IV Inverted V.
Correct Answer
A. Type II Gulf Coast.Explanation
The Gulf Coast is known for its warm and moist climate, making it a suitable region for a tropical airmass. The other options, such as the Great Plains, Pacific Coast, and Inverted V, do not typically have the same warm and moist characteristics as the Gulf Coast. Therefore, Type II Gulf Coast is the correct answer.Rate this question:
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- 20.
Which type of airmass has cold air at all levels?
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Type I Great Plains.
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Type II Gulf Coast.
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Type III Pacific Coast.
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Type IV Inverted V.
Correct Answer
A. Type III Pacific Coast.Explanation
Type III Pacific Coast airmass has cold air at all levels. This is because the Pacific Coast is influenced by the cold ocean currents, which results in the airmass being cooled from below. As a result, the airmass remains cold at all levels, making Type III the correct answer.Rate this question:
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- 21.
Which air mass is cold with surface temperatures ranging from 50°F to 68°F, the relative humidity commonly exceeding 70 percent at all levels up to at least 500mb, and average windspeeds of 15 knots at 850mb and 50 knots at 500mb?
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Type II Gulf Coast.
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Type I Great Plains.
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Type III Pacific Coast.
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Type IV Inverted V.
Correct Answer
A. Type III Pacific Coast.Explanation
The given description of the air mass matches the characteristics of Type III Pacific Coast. This air mass is cold with surface temperatures ranging from 50°F to 68°F, has high relative humidity at all levels, and average windspeeds of 15 knots at 850mb and 50 knots at 500mb. Therefore, the correct answer is Type III Pacific Coast.Rate this question:
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- 22.
Which type of airmass features maritime polar air overrunning continental tropical air between 5,000 and 8,000 feet above the surface?
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Type II Gulf Coast.
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Type I Great Plains.
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Type IV Inverted V.
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Type III Pacific Coast.
Correct Answer
A. Type IV Inverted V.Explanation
The correct answer is Type IV Inverted V. This type of airmass occurs when maritime polar air moves over continental tropical air at an altitude of 5,000 to 8,000 feet above the surface. The term "Inverted V" refers to the shape of the temperature profile in the atmosphere, with a warm layer aloft and cooler air below. This type of airmass is commonly found in certain regions, such as the Gulf Coast, where warm, moist air from the Gulf of Mexico interacts with drier air from the southwest.Rate this question:
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- 23.
What kind of dew-point temperature difference should exist across a dry line?
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< 10o F degrees.
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> 10oF degrees.
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< 10oC degrees.
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> 10oC degrees.
Correct Answer
A. > 10oF degrees.Explanation
A dew-point temperature difference of greater than 10oF degrees should exist across a dry line. This indicates that there is a significant difference in moisture content between the air masses on either side of the dry line. The dry line is a boundary that separates moist air from dry air, and the larger the dew-point temperature difference across the dry line, the more pronounced the difference in moisture content between the two air masses.Rate this question:
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- 24.
What severe weather synoptic pattern’s airmass is typically Type III?
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Type C, overrunning.
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Type D, cold core.
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Type A, dry line.
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Type B, frontal.
Correct Answer
A. Type D, cold core.Explanation
The correct answer is Type D, cold core. A cold core airmass refers to an airmass that is colder than the surrounding air at the same level. This type of airmass is typically associated with severe weather patterns such as thunderstorms and tornadoes. Therefore, it is likely that the severe weather synoptic pattern with a Type III airmass would be characterized by a cold core airmass.Rate this question:
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- 25.
When does the maximum severe activity occur with a major cyclone?
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A few hours after sunrise to maximum heating.
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From time of maximum heating to a few hours after sunset.
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Just before and after maximum heating.
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Only during maximum heating.
Correct Answer
A. From time of maximum heating to a few hours after sunset.Explanation
The maximum severe activity occurs with a major cyclone from the time of maximum heating to a few hours after sunset. This is because during this period, the temperature is at its highest, which leads to increased atmospheric instability and energy for the cyclone to intensify. As the sun sets and the temperature starts to decrease, the severe activity gradually diminishes.Rate this question:
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- 26.
What wind speeds do you focus on at the 200 and 30 millibar level for severe weather analysis?
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76 knots
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80 knots.
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86 knots.
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90 knots.
Correct Answer
A. 86 knots.Explanation
The wind speeds that are focused on at the 200 and 30 millibar level for severe weather analysis are 86 knots.Rate this question:
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- 27.
In straight line flow, what quadrants are the main diffluent areas of a jet maximum?
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Left & right rear.
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Left & right front.
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Left front & right rear.
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Left rear & right front.
Correct Answer
A. Left front & right rear.Explanation
In straight line flow, the main diffluent areas of a jet are the left front and right rear quadrants. This means that the jet is spreading out more in these areas compared to the other quadrants.Rate this question:
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- 28.
Which quadrant in the jet max should you look for positive vorticity advection?
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Left rear.
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Right rear.
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Left front.
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Right front.
Correct Answer
A. Right rear.Explanation
In the jet stream, vorticity advection refers to the change in vorticity (the measure of the rotation of fluid particles) with respect to time. Positive vorticity advection indicates that vorticity is increasing, which is commonly associated with the strengthening of weather systems. The right rear quadrant of the jet max is where the strongest positive vorticity advection is typically found. This is because the right rear quadrant is on the right side of the jet stream's maximum wind speed, where the wind is converging and causing the vorticity to increase.Rate this question:
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- 29.
At which pressure level is strong wind needed for thunderstorms to become severe?
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300 millibars.
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500 millibars.
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700 millibars.
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850 millibars.
Correct Answer
A. 500 millibars.Explanation
Strong wind is needed for thunderstorms to become severe. The given question asks at which pressure level this strong wind is needed. The correct answer is 500 millibars. This indicates that at a pressure level of 500 millibars, the wind is strong enough to cause severe thunderstorms.Rate this question:
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- 30.
What does positive vorticity advection indicate?
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Divergence or upward vertical motion.
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Convergence or upward vertical motion.
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Divergence or downward vertical motion.
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Convergence or downward vertical motion.
Correct Answer
A. Divergence or upward vertical motion.Explanation
Positive vorticity advection indicates divergence or upward vertical motion. Vorticity is a measure of the rotation of fluid particles in a fluid flow. Positive vorticity advection means that areas with higher vorticity are moving into an area with lower vorticity, which leads to divergence or spreading out of fluid particles. This divergence is often associated with upward vertical motion in the atmosphere, as air rises and spreads out.Rate this question:
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- 31.
What parameters are the two most important to analyze at 700 millibars?
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No-change line and dry-air intrusion.
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No-change line and wind maximums.
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Dew point temperatures and dry-air intrusion.
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Wind maximums and dew point temperatures.
Correct Answer
A. No-change line and dry-air intrusion.Explanation
At 700 millibars, the two most important parameters to analyze are the no-change line and dry-air intrusion. The no-change line represents the boundary between two air masses with different characteristics, such as temperature or moisture content, and can indicate potential weather changes. Dry-air intrusion refers to the intrusion of drier air into a region, which can affect atmospheric stability and precipitation patterns. Analyzing these parameters can provide valuable insights into weather patterns and potential weather changes at 700 millibars.Rate this question:
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- 32.
What weather characteristic does the 700 millibars no change line usually line up with?
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Trough axis.
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Surface front.
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Low-level jet.
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850 millibar warm ridge.
Correct Answer
A. 850 millibar warm ridge.Explanation
The 700 millibars no change line usually lines up with the 850 millibar warm ridge.Rate this question:
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- 33.
Which zone is not a type of surface convergent zone?
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Dry line.
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Frontal boundary.
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Land breeze front.
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Outflow boundary.
Correct Answer
A. Land breeze front.Explanation
A land breeze front is not a type of surface convergent zone. Surface convergent zones, such as dry lines, frontal boundaries, and outflow boundaries, occur when air masses with different characteristics come together and interact. However, a land breeze front refers to the boundary between cooler air over land and warmer air over water, which is a result of differential heating and not a convergence of air masses.Rate this question:
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- 34.
How far ahead of a cold front do pre-frontal squall lines form?
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25 to 125 statute miles.
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50 to 150 statute miles.
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25 to 125 nautical miles.
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50 to 150 nautical miles.
Correct Answer
A. 50 to 150 nautical miles.Explanation
Pre-frontal squall lines are known to form between 50 to 150 nautical miles ahead of a cold front.Rate this question:
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- 35.
What does a >+1 on the Showalter stability index suggest?
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Strong stability.
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Strong instability.
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Moderate stability.
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Moderate instability.
Correct Answer
A. Moderate stability.Explanation
A "+1" on the Showalter stability index suggests moderate stability. This means that the system or process being evaluated is relatively stable, but not to the extent of being considered strong stability. Moderate stability indicates that there may be some fluctuations or variations, but overall the system or process is fairly stable and not prone to significant instability.Rate this question:
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- 36.
What does a lifted index (LI) greater than zero indicate?
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Stability.
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Instability.
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No severe weather - winds too strong.
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Severe weather likely, chance of tornadoes.
Correct Answer
A. Stability.Explanation
A lifted index (LI) greater than zero indicates stability. Stability refers to atmospheric conditions where air parcels tend to resist vertical motion. This means that the atmosphere is more likely to be calm and less prone to severe weather events such as thunderstorms or tornadoes.Rate this question:
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- 37.
What weather occurrence does a severe weather threat index of 650 indicate?
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Severe thunderstorms likely, chance of tornadoes.
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Severe thunderstorms and tornadoes likely.
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No severe weather – winds too strong.
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Tornadoes nearly always occur.
Correct Answer
A. Tornadoes nearly always occur.Explanation
A severe weather threat index of 650 indicates that tornadoes nearly always occur. This means that the weather conditions are highly favorable for tornado formation and the likelihood of tornadoes is extremely high.Rate this question:
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- 38.
What atmospheric event does a negative convective available potential energy indicate?
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Increased warm moist air advection.
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Decreased cold dry air advection.
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Downward vertical motions.
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Upward vertical motions.
Correct Answer
A. Downward vertical motions.Explanation
A negative convective available potential energy indicates downward vertical motions in the atmosphere. This means that the air is sinking, which can lead to stable atmospheric conditions and inhibit the formation of storms or convective activity.Rate this question:
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- 39.
What weather feature is commonly found south of the center of a low pressure system and is indicated by a relatively cloud-free region?
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Warm front.
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Cold front.
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Dry line.
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Dry slot.
Correct Answer
A. Dry slot.Explanation
A dry slot is commonly found south of the center of a low pressure system and is indicated by a relatively cloud-free region. It is a region of dry air that wraps around the low pressure system and can bring clear skies and drier conditions. This is in contrast to the other options, as a warm front is associated with warm air rising over cold air, a cold front is associated with cold air advancing towards warm air, and a dry line is a boundary between moist and dry air masses.Rate this question:
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- 40.
Which atmospheric occurrence is not a type of lifting mechanism for convection?
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Convection.
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Frontal lifting.
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Decompression.
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Orographic lifting.
Correct Answer
A. Decompression.Explanation
Decompression is not a type of lifting mechanism for convection. Convection refers to the transfer of heat through the movement of fluids, such as air or water. In the context of the atmosphere, convection occurs when warm air rises and cooler air sinks. Frontal lifting occurs when warm and cold air masses collide, causing the warm air to be forced upward. Orographic lifting happens when air is forced to rise over a mountain or elevated terrain. However, decompression does not involve the upward movement of air. Instead, it refers to a decrease in atmospheric pressure, which can occur at high altitudes or in low-pressure systems.Rate this question:
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- 41.
What number of feet must the freezing level be for most precipitation to reach the surface as snow?
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1,000.
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1,100.
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1,200.
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1,300.
Correct Answer
A. 1,200.Explanation
The freezing level refers to the altitude at which the temperature drops below freezing. In order for precipitation to reach the surface as snow, the freezing level must be at or below the surface level. Among the given options, the freezing level of 1,200 feet is the closest to the surface level, making it the correct answer.Rate this question:
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- 42.
For the Weather Service Radar (WSR)–88D to generate a base reflectivity product, the antenna must complete
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One elevation slice.
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One complete 360° circle.
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An entire volume coverage pattern.
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At least two complete volume coverage patterns.
Correct Answer
A. One elevation slice.Explanation
The correct answer is one elevation slice. In order for the Weather Service Radar (WSR)-88D to generate a base reflectivity product, the antenna needs to complete one elevation slice. This means that the radar antenna scans a single vertical slice of the atmosphere at a specific elevation angle. This allows the radar to gather information about the reflectivity of precipitation in that particular slice of the atmosphere.Rate this question:
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- 43.
Which decibel (dBZ) value is considered the approximate precipitable/non-precipitable threshold?
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–30 dBZ.
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–18 dBZ.
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+18 dBZ.
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+30 dBZ.
Correct Answer
A. +18 dBZ.Explanation
The approximate precipitable/non-precipitable threshold is considered to be +18 dBZ. This means that any value below +18 dBZ is likely to indicate non-precipitation, while any value above +18 dBZ is likely to indicate precipitation.Rate this question:
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- 44.
What does the line echo wave pattern (LEWP) signature mean to a forecaster?
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A favorable environment exists for severe weather development.
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High pressure is forming and the threat of severe weather has ended.
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Continued thunderstorm development is certain but severe weather is unlikely.
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The current state of the atmosphere is much too stable for severe weather development.
Correct Answer
A. A favorable environment exists for severe weather development.Explanation
The line echo wave pattern (LEWP) signature indicates a favorable environment for severe weather development. This means that conditions are conducive for the formation of severe weather events such as thunderstorms, tornadoes, or heavy rainfall. The LEWP signature is a valuable tool for forecasters as it helps them identify areas where severe weather is likely to occur, allowing them to issue appropriate warnings and take necessary precautions.Rate this question:
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- 45.
Embedded thunderstorms are detected by the Weather Service Radar (WSR)–88D quite well because
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It uses airborne radar technology to seek out these storms.
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The storms move much faster than the surrounding precipitation.
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Its 10cm wavelength can see through the stratiform precipitation.
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The storms move much slower than the surrounding precipitation.
Correct Answer
A. Its 10cm wavelength can see through the stratiform precipitation.Explanation
The correct answer is "its 10cm wavelength can see through the stratiform precipitation." The Weather Service Radar (WSR)–88D is able to detect embedded thunderstorms well because it uses a 10cm wavelength that can penetrate through the stratiform precipitation. This allows the radar to see the thunderstorms that are hidden within the surrounding precipitation.Rate this question:
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- 46.
Outflow boundaries may be seen on the Weather Service Radar (WSR)–88D even when no clouds are present because
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The WSR–88D can detect returns of greater than +18dBZ.
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Precipitable water is present although it is not visible to the human eye.
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Low-level wind shear is usually present with the boundary, making it more visible.
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A gradient in the refractive index due to density differences that exist with the boundary.
Correct Answer
A. A gradient in the refractive index due to density differences that exist with the boundary.Explanation
The correct answer is a gradient in the refractive index due to density differences that exist with the boundary. Outflow boundaries can be detected on the Weather Service Radar (WSR) – 88D even when no clouds are present because they create a gradient in the refractive index. This gradient is caused by density differences between the outflow boundary and the surrounding air. The radar can detect this gradient and display it as a return on the radar screen, even if there are no visible clouds in the area.Rate this question:
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- 47.
Which product is used in the detection and location of rotating thunderstorms and in determining wind field characteristics?
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Base reflectivity.
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Base radial velocity.
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Severe weather analysis.
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Severe weather probability.
Correct Answer
A. Base radial velocity.Explanation
Base radial velocity is used in the detection and location of rotating thunderstorms and in determining wind field characteristics. Radial velocity measures the speed and direction of motion of precipitation particles towards or away from the radar. By analyzing the radial velocity data, meteorologists can identify areas of rotation within thunderstorms, which can indicate the potential for tornado development. Additionally, the wind field characteristics can be determined by examining the radial velocity patterns, helping meteorologists understand the overall storm structure and dynamics.Rate this question:
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- 48.
When the Doppler zero line has a noticeable S-shaped pattern, winds are considered to be
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From 270°.
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Veering with height.
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Backing with height.
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Increasing with height.
Correct Answer
A. Veering with height.Explanation
The Doppler zero line is a line on a Doppler radar display that represents the location where there is no motion towards or away from the radar. When the Doppler zero line has a noticeable S-shaped pattern, it indicates that the winds are changing direction with height. This is known as veering with height. Veering refers to a clockwise change in wind direction with increasing height. Therefore, the correct answer is veering with height.Rate this question:
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- 49.
Which concept should be considered when trying to determine hail size?
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Strength of the updraft.
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Rotation at the base of the storm.
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Strength of the convergence aloft.
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Rotation in the mid-levels of the storm.
Correct Answer
A. Strength of the updraft.Explanation
When trying to determine hail size, the concept that should be considered is the strength of the updraft. The updraft is the upward movement of air within a storm, and it plays a crucial role in the formation of hail. A strong updraft can carry water droplets higher into the storm, allowing them to freeze and grow larger before falling to the ground as hailstones. Therefore, the strength of the updraft is directly related to the size of the hailstones that can be produced.Rate this question:
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Mar 22, 2023Quiz Edited by
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Feb 17, 2014Quiz Created by
Daronwilli
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