Question 1

A prog is
A) a chart that interprets the current state of the atmosphere.
B) an instrument that draws lines on an upper-level chart.
C) a new method of forecasting the weather.
D) a forecast chart that shows the atmosphere at some future time.
E) another name for a probability forecast.

Accepted Answer

A prog is a forecast chart that shows the atmosphere at some future time.

Question 2

A forecast of an extended period of dry weather would be made for a region beneath
A) an upper-level trough.
B) the polar jet stream.
C) a cold pool of air aloft.
D) an upper-level ridge.
E) a shortwave trough.

Accepted Answer

An upper-level ridge typically leads to sinking air and high pressure at the surface, creating dry and stable conditions. Therefore, a forecast of an extended period of dry weather would be made for a region beneath an upper-level ridge.

Question 3

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 occurring within the 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.

Accepted Answer

A weather warning is issued when hazardous weather is either imminent or occurring within the forecast area. It is a more urgent and severe level of warning compared to a watch, which indicates that the atmospheric conditions are favorable for hazardous weather. Option A is describing a watch, not a warning. Option C is too broad and does not specify when the hazardous weather is likely to occur. Option D is not a complete definition of a weather warning.

Question 4

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) redundancy analysis.
C) persistence forecasting.
D) ensemble forecasting.
E) probability forecasting.

Accepted Answer

The forecasting technique described is called ensemble forecasting. A set of slightly varied forecast models are created to account for potential errors in the initial weather measurements. The different versions of the forecast are then combined to create a more accurate prediction.

Question 5

For a forecast to show skill it must
A) be better than one based on persistence or climatology.
B) be accurate to within 2 C of the predicted temperature.
C) be accurate for over more than 90 percent of the forecast area.
D) use the analogue method of forecasting.
E) use a probability.

Accepted Answer

Skill in a forecast is measured by its ability to outperform a forecast based on persistence (just assuming the same conditions as the previous day) or climatology (long-term averages). Therefore, option A is the correct answer. The other options, such as accuracy within a specific range or percentage, or using a particular forecasting method, do not necessarily indicate skill.

Question 6

Which forecasting method assumes that weather systems will move in the same direction and at the same speed as they have been moving?
A) persistence forecast
B) probability forecast
C) weather type forecast
D) climatological forecast
E) steady state (trend)forecast

Accepted Answer

The answer of Which forecasting method assumes that weather systems...

Question 7

A weather forecast for the immediate future that employs the trend method is called
A) nowcasting.
B) extrapolation.
C) first order forecast.
D) linear forecast.

Accepted Answer

Nowcasting is a weather forecasting technique that predicts the immediate future, typically up to a few hours ahead, using current weather data and trends.

Question 8

A weather watch would probably be issued for which of the following conditions?
A) There is a chance for tornadoes tomorrow.
B) Presently,extremely high winds are occurring at mountain summits.
C) A tornado has been sighted at the outskirts of town.
D) Heavy snow has been falling over the forecast area.

Accepted Answer

A weather watch is typically issued when there is a possibility of severe weather occurring within a certain timeframe. In this case, the possibility of tornadoes tomorrow would warrant a weather watch. The other options either describe current weather conditions (B) or a confirmed severe weather event (C) which would typically trigger a weather warning instead of a watch. D) Heavy snowfall would warrant a winter weather advisory or warning instead of a weather watch.

Question 9

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) forecast based on the analogue method.
B) persistence forecast.
C) forecast based on weather types.
D) probability forecast.
E) climatological forecast.

Accepted Answer

The forecast of a "January thaw" occurring in the middle of January is based on the climatological pattern in the region, rather than any specific weather patterns or events. Therefore, it is a climatological forecast.

Question 10

A forecast method that compares past weather maps and weather patterns to those of the present is
A) persistence forecasting.
B) the analogue method.
C) the trend method.
D) nowcasting.

Accepted Answer

The analogue method compares current weather conditions to those observed in the past in order to develop a forecast. This method is useful when historical weather patterns and data are available. Persistence forecasting is basing a forecast solely on the current conditions, without consideration of past weather patterns. The trend method involves using statistical models to analyze past weather data and determine trends. Nowcasting involves making short-term forecasts (usually up to six hours) based on current weather conditions and radar and satellite data.

Question 11

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 rain.
C) it will rain on 40 percent of the forecast area.
D) it will rain during 40 percent of the time over the forecast area.

Accepted Answer

A "40 percent chance of rain" means that out of 100 random samples of the forecast area with the same weather conditions, rain would occur in 40 of them, and not occur in 60 of them. Therefore, there is a 40 percent chance that any random place in the forecast area will receive measurable rain. Option A is incorrect because it implies that there is a 60 percent chance that it will rain, which is not the case. Option C is incorrect because it suggests that only 40 percent of the area is expected to receive rain, which is not necessarily true. Option D is incorrect because it suggests that it will rain for 40 percent of the forecast period, which is not specified in the given forecast.

Question 12

An analysis is
A) a forecast chart that shows the atmosphere at some future time.
B) a forecast chart that compares past weather maps with those of the present.
C) a surface or upper-level chart that interprets the present weather patterns.
D) a forecast method used in long range weather prediction.
E) a method used to determine skill in predicting the weather.

Accepted Answer

An analysis is a surface or upper-level chart that interprets the present weather patterns. It helps meteorologists to understand the current atmospheric conditions and make accurate forecasts. Choices A, B, D, and E are incorrect because they do not accurately describe an analysis.

Question 13

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

Accepted Answer

An accurate forecast can be the result of skill, however, it can also be due to luck or chance. It may require complex computer equipment, but this is not always necessary for an accurate forecast.

Question 14

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.

Accepted Answer

Persistence forecasting is based on the assumption that the weather conditions will remain the same as the previous day(s). Therefore, if you are positioned in the middle of a large, stationary air mass, the persistence forecast is likely to be quite accurate as the weather is unlikely to change significantly.

Question 15

Weather forecast that predicts that the future weather will be the same as the present weather is called
A) a steady-state forecast.
B) the trend method.
C) a persistence forecast.
D) the analogue method.
E) an extended weather forecast.

Accepted Answer

A persistence forecast predicts that the future weather will be the same as the present weather, assuming that there are no significant changes in the atmosphere. This method is often used for short-term forecasting because it assumes that weather patterns will continue unchanged over a short period of time.

Question 16

By examining a surface map,the movement of a surface low pressure area can be predicted based upon the
A) orientation of the isobars in the warm sector.
B) region of greatest pressure decrease.
C) movement during the previous 6 hours.
D) all of the above

Accepted Answer

All of the listed factors can provide information that can be used to predict the movement of a surface low pressure area. The orientation of isobars in the warm sector can indicate the direction of air flow and can help predict the direction of movement. The region of greatest pressure decrease is often located to the north and east of the low pressure center and can also provide information on the direction of movement. The movement during the previous 6 hours can provide information on the speed and direction of movement, which can be used to make predictions about future movement.

Question 17

Which of the following is presently a problem with modern-day weather predictions?
A) Computer forecast models make assumptions about the atmosphere that are not always correct.
B) There are regions of the world where only space observations are available.
C) Computer models do not always adequately interpret the surface's influence on the weather.
D) The distance between grid points on some models is too large to pick up smaller-scale weather features such as thunderstorms.
E) all of the above

Accepted Answer

All of the given options are presently a problem with modern-day weather predictions. Computer forecast models make assumptions about the atmosphere that are not always accurate, regions of the world only have access to space observations, computer models struggle to interpret the surface's influence on weather, and the distance between grid points on some models can be too large to pick up smaller-scale weather features such as thunderstorms.

Question 18

Suppose it is warm and raining,and a cold front is moving toward your location.Directly behind the cold front,it is cold and snowing.Still further behind the front,the weather is cold and clearing.If the front is scheduled to pass your area in 6 hours,a persistence forecast for your area for 12 hours from now would be
A) cold and snowing.
B) cold and clearing.
C) cold and cloudy.
D) warm and raining.
E) not enough information on which to base a forecast

Accepted Answer

A persistence forecast assumes that the current weather conditions will continue unchanged. Since it is currently warm and raining, a persistence forecast for 12 hours from now would predict the same conditions.

Question 19

Predicting the weather by weather types employs which forecasting method?
A) probability
B) steady-state
C) analogue
D) persistence
E) guess

Accepted Answer

Predicting the weather by weather types uses the analogue forecasting method, which involves comparing current weather conditions to past similar weather patterns to make a prediction. Probability forecasting involves assigning likelihoods to future events based on statistical analysis, steady-state forecasting assumes constant conditions, persistence forecasting involves assuming that current conditions will persist, and guess forecasting involves making a prediction without any supporting data.

Question 20

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) prediction by weather types.
E) numerical weather prediction.

Accepted Answer

The persistence forecast is based on the assumption that conditions will remain the same as the current conditions. However, during changeable weather conditions, this method is not very accurate as conditions can rapidly change. The other methods listed, such as the analogue method and prediction by weather types, involve using historical patterns and patterns of similar weather conditions, respectively, which can be more accurate in predicting changes in the weather. Numerical weather prediction involves using computer models and can be highly accurate, but it requires a lot of data and resources, making it less practical for forecasting only two days into the future.

Quiz 13: Weather Forecasting

A prog is

A forecast of an extended period of dry weather would be made for a region beneath

A weather warning indicates that

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

For a forecast to show skill it must

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

A weather forecast for the immediate future that employs the trend method is called

A weather watch would probably be issued for which of the following conditions?

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

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

An analysis is

An accurate forecast

A persistence forecast could be quite accurate when

Weather forecast that predicts that the future weather will be the same as the present weather is called

By examining a surface map,the movement of a surface low pressure area can be predicted based upon the

Which of the following is presently a problem with modern-day weather predictions?

Predicting the weather by weather types employs which forecasting method?

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