MET 121 Final Exam
1. What is the function of the National Center for
Environmental Prediction?: - The National Center for
Environmental Prediction (NCEP) receives global weather data
from several world meteorological centers many times each day.
The data are analyzed and plotted, and forecasts are prepared and
transmitted to National Center for Environmental Prediction
(NCEP).
2. How does a weather watch differ from a weather warning?:
Weather watch- Indicates that atmospheric conditions favor
hazardous weather occurring over a particular region during a
specified time period. These hazards may or may not actually
develop, and their timing and location are uncertain, so a watch
simply means be on "watch" for that threat and to be prepared to
act if necessary
,Weather Warning- Indicates that the hazard now occurring or
imminent is considered to be a threat to life and/or property
(tornadoes, thunderstorms, etc)
3. List at least four tools a weather forecaster might use when
making a short-range forecast: Doppler radar, surface weather,
maps & upper air winds
4. How does a prog differ from an analysis?: Analysis is what
is going on right now and a prog is a forecast
5. In what ways have high-speed computers assisted the
meteorologist in making weather forecasts?: Computer-
generated weather forecasts can analyze large quantities of data
extremely fast. Each day the many thousands of observations
transmitted to NCEP are fed into a high-speed computer, which
plots and draws lines on surface and upper-air charts.
Meteorologists interpret the weather patterns and then correct any
errors that may be present. The routine daily forecasting of
weather by the computer has come to be known as numerical
weather prediction. To help forecasters handle all the available
,charts and maps, high-speed data modeling systems using
computers are employed.
6. How are computer-generated forecasts prepared?: The
models are pro- grammed into the computer, and surface and
upper-air observations of temperature, pressure, moisture, winds,
and air density are fed into the equations. To determine how each
of these variables will change, each equation is solved for a small
increment of future time, say, 5 minutes, for a large number of
locations called grid points; each situated a given distance apart.
In addition, each equation is solved for as many as 50 levels in the
atmosphere. The results of these computations are then fed back
into the original equations. The computer again solves the
equations with the new "data," thus predicting weather over the
following 5 minutes. The computer then analyzes the data and
draws the projected positions of pressure systems with their
isobars or contour lines.
7. What are some of the problems associated with computer-
model fore- casts?: Observations over uninhabited regions
, Weather systems crossing boundaries of models
Forecasting small scale evens with larger grids
8. 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, what type of weather forecast will you have made?:
Climatological
9. Describe four methods of forecasting the weather and give
an example for each one: Persistence Forecasts- A prediction that
future weather will be the same as present weather
Steady-state- Surface weather systems tend to move in same
direction and at approximately the same speed as they have been
moving, providing no evidence exists to indicate otherwise
1. What is the function of the National Center for
Environmental Prediction?: - The National Center for
Environmental Prediction (NCEP) receives global weather data
from several world meteorological centers many times each day.
The data are analyzed and plotted, and forecasts are prepared and
transmitted to National Center for Environmental Prediction
(NCEP).
2. How does a weather watch differ from a weather warning?:
Weather watch- Indicates that atmospheric conditions favor
hazardous weather occurring over a particular region during a
specified time period. These hazards may or may not actually
develop, and their timing and location are uncertain, so a watch
simply means be on "watch" for that threat and to be prepared to
act if necessary
,Weather Warning- Indicates that the hazard now occurring or
imminent is considered to be a threat to life and/or property
(tornadoes, thunderstorms, etc)
3. List at least four tools a weather forecaster might use when
making a short-range forecast: Doppler radar, surface weather,
maps & upper air winds
4. How does a prog differ from an analysis?: Analysis is what
is going on right now and a prog is a forecast
5. In what ways have high-speed computers assisted the
meteorologist in making weather forecasts?: Computer-
generated weather forecasts can analyze large quantities of data
extremely fast. Each day the many thousands of observations
transmitted to NCEP are fed into a high-speed computer, which
plots and draws lines on surface and upper-air charts.
Meteorologists interpret the weather patterns and then correct any
errors that may be present. The routine daily forecasting of
weather by the computer has come to be known as numerical
weather prediction. To help forecasters handle all the available
,charts and maps, high-speed data modeling systems using
computers are employed.
6. How are computer-generated forecasts prepared?: The
models are pro- grammed into the computer, and surface and
upper-air observations of temperature, pressure, moisture, winds,
and air density are fed into the equations. To determine how each
of these variables will change, each equation is solved for a small
increment of future time, say, 5 minutes, for a large number of
locations called grid points; each situated a given distance apart.
In addition, each equation is solved for as many as 50 levels in the
atmosphere. The results of these computations are then fed back
into the original equations. The computer again solves the
equations with the new "data," thus predicting weather over the
following 5 minutes. The computer then analyzes the data and
draws the projected positions of pressure systems with their
isobars or contour lines.
7. What are some of the problems associated with computer-
model fore- casts?: Observations over uninhabited regions
, Weather systems crossing boundaries of models
Forecasting small scale evens with larger grids
8. 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, what type of weather forecast will you have made?:
Climatological
9. Describe four methods of forecasting the weather and give
an example for each one: Persistence Forecasts- A prediction that
future weather will be the same as present weather
Steady-state- Surface weather systems tend to move in same
direction and at approximately the same speed as they have been
moving, providing no evidence exists to indicate otherwise