Deck 9: Weather Forecasting

Question 1

A weather warning indicates that ____.

A) the atmospheric conditions are favorable for hazardous weather over a particular region
B) hazardous weather is either imminent or actually occurring within the specified forecast area
C) hazardous weather is likely to occur within the forecast area during the next 24 hours
D) hazardous weather is frequently observed in a particular region

Answer 1

B

Question 2

A weather forecast that predicts that future weather will be the same as present weather is called ____.

A) a steady-state forecast
B) the trend method
C) a persistence forecast
D) the analogue method

Answer 2

C

Question 3

A chart that plots how air temperature has changed over the past five days at a given station would be a(n) ____.

A) sounding
B) meteogram
C) atmospheric model
D) ensemble forecast

Answer 3

B

Question 4

Suppose that where you live the middle of January is typically several degrees warmer than the rest of the month. If you forecast this "January thaw" for the middle of next January, you would have made a ____.

A) climatological forecast
B) persistence forecast
C) forecast based on weather types
D) statistical forecast

Question 5

An accurate forecast ____.

A) always shows skill
B) may or may not show skill
C) never shows skill
D) requires complex computer equipment

Question 6

If you wanted to make a persistence forecast of minimum and maximum temperatures for a particular city, which type of chart would be most helpful?

A) surface chart
B) meteogram
C) 500-mb chart
D) Doppler radar display

Question 7

A weather watch would most likely issued for which condition?

A) There is a chance for tornadoes today.
B) Severe thunderstorms have been spotted in the forecast area.
C) Presently, extremely high winds are occurring at mountain summits.
D) A tornado has been sighted at the outskirts of town.

Question 8

A forecast method that compares past weather maps and weather patterns to those of the present is ____.

A) the persistence forecast
B) the analogue method
C) the trend method
D) steady-state forecast

Question 9

A probability forecast that calls for a "40 percent chance of rain" means that ____.

A) there is a 40 percent chance that it will not rain within the forecast area
B) there is a 40 percent chance that any random place in the forecast area will receive measurable rainfall
C) it will rain on 40 percent of the forecast area
D) it will rain 40 percent of the time over the forecast area

Question 10

A nowcast is a weather forecast that extends for ____.

A) 1-2 days
B) usually not more than 6 hours
C) 3 days or more
D) 3 to 8 days

Question 11

An ensemble forecast is considered robust when the ____.

A) weather situation is rather complicated
B) progs match each other fairly well
C) ensemble forecast chart looks like scrambled spaghetti
D) progs have many different contour lines

Question 12

A weather prediction for the United States based on El Niño events is an example of forecasting using ____.

A) persistence
B) teleconnections
C) statistics
D) probabilities

Question 13

What is one of the greatest improvements in forecasting skill over the past decade?

A) predicting the strength and path of snowstorms along the eastern seaboard
B) increasing the lead time for watches and warnings for severe storms
C) predicting the movement of warm and cold fronts
D) estimating maximum and minimum temperatures 6 to 10 days in the future

Question 14

Probability forecasts use climatological data that are typically averaged over ___ years.

A) 2
B) 30
C) 10
D) 16

Question 15

Smaller grid spacing ____ the resolution of computer forecasting models.

A) can decrease
B) does not change
C) can increase
D) can vary

Question 16

Predicting the weather by weather types employs which forecasting method?

A) probability
B) steady-state
C) analogue
D) persistence

Question 17

Forecast models have a hard time predicting ____.

A) temperature
B) jet stream patterns
C) precipitation
D) surface pressure

Question 18

Which forecasting method assumes that weather systems will move in the same direction and at approximately the same speed as they have been moving?

A) persistence forecast
B) probability forecast
C) steady-state (trend) forecast
D) climatological forecast

Question 19

Large-scale computer models would typically have ____ grid spacing compared to small-scale models.

A) shorter
B) longer
C) the same
D) varied

Question 20

The forecasting technique that produces several versions of a forecast model, each beginning with slightly different weather information to reflect errors in the measurements, is called ____.

A) climatology forecasting
B) probability forecasting
C) persistence forecasting
D) ensemble forecasting

Question 21

Exhibit 9-1 The following questions refer to the above illustration of a mid-latitude cyclone (the dashed lines show the positions of the fronts 6 hours ago). Consider the accompanying figure. At which of the four positions would you expect to hear the following 12-hour forecast?

A) 1
B) 2
C) 3
D) 4

Question 22

For a forecast to show ____, it should be better than one based solely on the current or the "normal" weather.

A) skill
B) accuracy
C) chaos
D) persistence

Question 23

Low pressure systems tend to move toward the region of greatest ____.

A) barometric pressure
B) surface pressure rise
C) surface pressure drop
D) visibility

Question 24

Exhibit 9-1 The following questions refer to the above illustration of a mid-latitude cyclone (the dashed lines show the positions of the fronts 6 hours ago). Consider the accompanying figure. At which of the four positions would you expect to hear the following 12-hour forecast?

A) 1
B) 2
C) 3
D) 4

Question 25

Continental polar air associated with a wintertime high pressure area will likely bring ____.

A) freezing temperatures
B) warm temperatures and rain
C) cloudy skies and a rare winter thunderstorm
D) a blizzard

Question 26

A persistence forecast could be quite accurate when ____.

A) a frontal system approaches your location at constant speed
B) you are positioned in the middle of a large, stationary air mass
C) the weather has been unusually cold for several days
D) upper level winds blow straight from west to east

Question 27

Low-pressure areas tend to ____ before occluding and ____ after occluding.

A) decelerate; accelerate
B) accelerate; decelerate
C) stop; accelerate
D) decelerate; stop

Question 28

A high pressure system that tends to persist in the same geographic location for many days is referred to as a ____.

A) static high
B) stationary high
C) blocking high
D) stable high

Question 29

Exhibit 9-1 The following questions refer to the above illustration of a mid-latitude cyclone (the dashed lines show the positions of the fronts 6 hours ago). The storm system in the accompanying figure will apparently move toward the ____.

A) northeast
B) east
C) southeast
D) northwest

Question 30

High pressure systems tend to move toward the region of greatest ____.

A) barometric pressure
B) surface pressure rise
C) surface pressure drop
D) visibility

Question 31

The least accurate forecast method of predicting the weather two days into the future during changeable weather conditions is usually the ____.

A) trend method
B) persistence forecast
C) analogue method
D) probability forecast

Question 32

With limited number of wind observations, tight spacing of height (above sea level) contour lines on a 500-mb chart may indicate areas of ____.

A) stationary winds
B) stronger winds
C) weaker winds
D) variable winds

Question 33

Exhibit 9-1 The following questions refer to the above illustration of a mid-latitude cyclone (the dashed lines show the positions of the fronts 6 hours ago). Consider the accompanying figure. At which of the four positions would you expect to hear the following 12-hour forecast?

A) 1
B) 2
C) 3
D) 4

Question 34

Surface pressure systems tend to move ____ the wind at the 500-mb level.

A) at the same speed as
B) much faster than
C) in the same direction as
D) in the opposite direction as

Question 35

A downslope wind coming off a mountain will ____ in a nearby city affected by a strong polar high-pressure system.

A) decrease snowfall
B) increase the temperature
C) decrease the temperature
D) have no affect

Question 36

Forecasting large-scale weather events several days in advance is ____.

A) rarely attempted
B) generally done with near-perfect accuracy
C) less accurate than forecasting the precise evolution and movement of small-scale, short-lived weather systems
D) more accurate than forecasting the precise evolution and movement of small-scale, short-lived weather systems

Question 37

The general area where a tornado is likely to form can often be predicted ____.

A) up to 3 days in advance
B) up to 7 days in advance
C) up to 10 days in advance
D) up to 14 days in advance

Question 38

If a mid-latitude cyclonic storm has moved from the southwest toward the northeast during the past six hours, the storm is likely to move toward the ____ during the next six hours.

A) northwest
B) southwest
C) southeast
D) northeast

Question 39

Beyond about ____, due to the chaotic nature of the atmosphere, computer prog forecast accuracy falls off rapidly.

A) 2 hours
B) 12 hours
C) 2 days
D) 7 days

Question 40

Exhibit 9-1 The following questions refer to the above illustration of a mid-latitude cyclone (the dashed lines show the positions of the fronts 6 hours ago). Consider the accompanying figure. At which of the four positions would you expect to hear the following 12-hour forecast?

A) 1
B) 2
C) 3
D) 4

Question 41

Instructions: Choose one answer from each pair of selections. You would expect a relatively WARM | COLD minimum temperature on a night with calm winds, clear skies, and low humidity.

Question 42

Geographical features on the earth such as mountain ranges do not have much effect on the weather because the features are small compared to the thickness of the atmosphere.

Question 43

Instructions: Choose one answer from each pair of selections. A WATCH | WARNING indicates that hazardous weather is either imminent or actually occurring within the specified forecast area.

Question 44

Instructions: Choose one answer from each pair of selections. Small errors in weather observations generally AMPLIFY | DIMINISH as computers predict weather farther and farther into the future

Question 45

Instructions: Choose one answer from each pair of selections. Forecasting large scale weather events is MORE | LESS accurate than smaller, shorter-lived events.

Question 46

A model is run several times with slight changes in the starting data. What type of forecast will be generated?

Question 47

Instructions: Choose one answer from each pair of selections. If you wanted to examine the location of ridges, troughs, and short waves in the atmosphere, which forecast chart would you use? SURFACE MAP | 500-MB

Question 48

Instructions: Choose one answer from each pair of selections. The halo around the moon (or sun) is caused by the bending of light as it passes through ice crystals in CIRROSTRATUS | CUMULUS clouds.

Question 49

The most widely separated surface weather observations come from what region on the earth?

Question 50

Weather observations made by most countries of the world are shared and distributed globally by international agencies.

Question 51

Most computer models produce forecasts for only one grid point.

Question 52

Instructions: Choose one answer from each pair of selections. A METEOGRAM | SOUNDING is a two-dimensional vertical profile of temperature, dew point, and winds.

Question 53

Instructions: Choose one answer from each pair of selections. Surface pressure systems tend to move in the same direction as the wind at 5500 m and at about THE SAME | HALF the speed.

Question 54

What are two commonly used terms for a computer-derived forecast map?

Question 55

A forecaster will use a prognostic chart for guidance in preparing a forecast, but will also rely on personal experience and a knowledge of local features that can affect the weather.

Question 56

Weather charts and maps are still plotted and analyzed entirely by hand.

Question 57

Instructions: Choose one answer from each pair of selections. A forecast chart representing the atmosphere at a specified future time is a(n) ANALYSIS | PROG.

Question 58

Instructions: Choose one answer from each pair of selections. A comma-shaped cloud above a low-pressure storm system indicates that the storm is DISSIPATING | DEEPENING.

Question 59

What are a set of mathematical equations that approximate how atmospheric temperature, pressure, winds, and moisture vary with time?

Question 60

Temperature and precipitation in one part of the world can affect the weather in another widely separated region. What are these interactions called?

Question 61

How are weather observations shared and distributed among different nations?

Question 62

Under what circumstances would the National Weather Service issue a tornado watch?

Question 63

List some of the ways in which you can predict the future movement of surface mid-latitude storms.

Question 64

Describe four different types of weather forecasting methods and give an example of each.

Question 65

List some of the factors that affect the accuracy of weather forecasts.