Meteorology Exam #4 Practice Exam
Terms in this set (95)
The initial stage of an ordinary cell thunderstorm is the
Ordinary cell thunderstorms only last about one hour and begin to dissipate when
when the downdraft spreads throughout the cloud and cuts off the updraft
A group of thunderstorms which develop in a line one next to the other, each in a different stage of development, are called
a multicell thunderstorm
The most turbulent part of a thunderstorm is
between the updraft and downdraft
A supercell storm is
an enormous thunderstorm that lasts for several hours.
Which of the following would you not expect to observe during the passage of a gust front?
increase in temperatures
Blowing dust moving outward at the ground below a thunderstorm could indicate a
A relatively narrow downburst, less than 4 kilometers wide, is called
On a surface weather map, this marks the boundary where a warm, dry air mass encounters a warm, moist air mass
The greatest annual number of thunderstorms in the United States occurs in
The most likely time for an ordinary cell thunderstorm to form is
Lightning discharges within a cloud occur ____
more frequently than
are negatively charged
The top of a thunderstorm is normally ____ charged, and the middle and lower parts are ____ charged
A cloud-to-ground lightning discharge will sometimes appear to flicker. This is because
you are able to distinguish separate return strokes
You are generally safe inside an automobile during a lighting storm because
the metal car body
will carry the lightning current around the passengers inside.
Thunder is caused by
the rapid heating of air surrounding a lightning channel
If you see a lightning stroke and then, 15 seconds later, hear the thunder, the lightning is about ____ miles away.
(1 mile per 5 seconds)
When caught in a thunderstorm in an open field, the best thing to do is to
crouch down as low as possible while minimizing contact with the ground.
Which of the following is the most accurate description of the principle of a lightning rod?
the lightning rod intercepts the lightning and safely carries the lightning current around the object it protects
A tornado cloud that does not touch the ground is called
a funnel cloud
Which of the following factors is most important in determining the strength of a tornado?
Which of the following statements about tornadoes is correct?
the United States has more tornadoes that any other country in the world
Which of the following regions would you expect to have the most tornadoes in the winter?
southern Gulf States
The Enhanced Fujita scale pertains to
the strength of a tornado
Most tornadoes have winds that are
less than 100 MPH
Most tornadoes move from
southwest to northeast
If a tornado is rotating in a counterclockwise direction and moving toward the northeast, the strongest winds will be on its ____ side.
A hook-shaped echo on a radar screen often indicates
the possible presence of a tornado-producing thunderstorm
____ measures the speed at which precipitation is moving toward or away from an observer.
The signal detected by a Doppler radar is
a radio wave reflected by precipitation
On a Doppler radar screen, a tornado might appear as a
a region of rapidly changing wind speeds
A Doppler radar determines precipitation ____ by measuring changes in the ____ of the reflected radio wave.
A tornado-like event that forms over water is a
During the summer, what conditions prevail near the surface over the Great Plains that help a hailstone
survive as ice all the way to the ground?
a warm, shallow layer of dry air
Which figure comes closest to the estimated number of thunderstorms that occur each year throughout the
In the United States,
are most common
in the Great Plains
Lightning may occur
within a cloud; from a cloud to the ground; from one cloud to another cloud
(All of the above)
The upper part of a thunderstorm cloud is normally ____ charged, and the middle and lower parts are ____ charged.
____ latent heat energy is available once tropical cyclones pass from water onto land
____ their life cycle, north Atlantic hurricanes are guided by the trade winds.
A typically hurricane produces ____ precipitation than a typical mid-latitude cyclone
Which of the following is
not true concerning an easterly wave?
has converging winds on its western side
The skies in the center (eye) of a hurricane are often cloud free. This is because the air in the eye
An intense storm of tropical origin that forms over the Pacific Ocean adjacent to the west coast of Mexico
would be called a
Pressure at the center of a hurricane is ____ than the surroundings at the surface and ____ than the
The vertical structure of the hurricane shows an upper-level ____ of air, and a surface ____ of air.
In the Northern Hemisphere, hurricanes and middle latitude cyclones are similar in that both
have winds that blow counterclockwise around their centers.
In a hurricane, the eye wall represents
a zone of intense thunderstorms around the center
Hurricane winds rotate in a clockwise direction
in the Southern Hemisphere only
At the periphery of a hurricane the air is ____, and several kilometers above the surface, in the eye, the air is
The surface pressure at the center of hurricane Gilbert decreased to a value of ____, the record minimum
value for Atlantic hurricanes.
The main reason hurricanes don't develop over the south Atlantic Ocean adjacent to South America is because
the surface water temperatures are too cold
As surface air rushes in toward the eye of a hurricane, the air expands and should cool. The main reason the surface air is not cooler around the eye is because
the warm water heats the air.
The main difference between a hurricane and a tropical storm is that
winds speeds are greater in a hurricane
Hurricanes dissipate when
they move over colder water;
they move over land; surface inflow of air exceeds upper-level outflow of air.
(All of the above)
A tropical storm becomes a hurricane when
the winds exceed 64 knots (74 MPH).
As a northward-moving hurricane passes to the east of an area, surface winds should change from
NE to N to NW.
Which method below describes how scientists have tried to modify hurricanes?
seeding the hurricanes with silver iodide
Which of the following areas in the United States would most likely experience thunderstorms, hurricanes and tornadoes during the course of one year?
Gulf Coast states
Which statement below is
not correct concerning hurricanes?
a hurricane moving northward over the Pacific will normally survive for a longer time than one moving north over the Atlantic
On the Saffir-Simpson hurricane scale, a hurricane with winds in excess of 155 mi/hr (135 knots) and a
central pressure of 910 mb (26.87 in.) would be
classified as a category ____ hurricane.
Which below is the best indication that a hurricane will likely strike your area within 24 hours?
a hurricane warning issued by the National Weather Service
On the Saffir-Simpson scale a category 5 storm would indicate
a very strong hurricane.
The strongest winds in a hurricane heading westward toward Florida would most likely be found on the ____ side
Most of the destruction caused by a hurricane is due to
A hurricane warning
gives the percent chance of a hurricane's center passing within 65 miles of a community
Storms that form in the tropics are given names when
they reach tropical storm strength
Suppose the eye of a hurricane passed directly over you, and you survived the experience. If winds were from the northeast as the eyewall first approached you, from what direction did the winds blow when the eyewall reached you the second time?
A strong trade wind inversion ____ to the development of a hurricane.
is not conducive
Hurricanes can't form along the equator because
the Coriolis force is too small along the equator
Typhoons and hurricanes
are the same type of tropical storm
Storm surge describes
an increase in ocean level
Category 1 hurricanes ____ category 5 hurricanes.
are much more common than
The west coast of Mexico's Yucatan peninsula receives ____ hurricanes than it's east coast.
In some situations individual thunderstorms may organize into a convective weather system that may be 1000 times larger than an individual storm.
Electrical charge is produced in thunderstorms by collisions between different types of precipitation particles.
Lightning is sometimes produced during snowstorms and dust storms, and by the clouds of erupting volcanoes
Most cloud-to-ground lightning flashes consist of a single return stroke.
Dim lightning discharges have been observed to shoot upward from the tops of thunderstorms into the upper atmosphere
Most tornadoes last only a few minutes; some tornadoes have existed for several hours.
When the air is dry tornado winds can remain invisible until they reach the ground and pick up dust.
Weak tornadoes sometimes form along a thunderstorm gust front.
An upper level inversion may actually favor severe thunderstorm development because the inversion will
prevent many smaller weaker thunderstorms from forming.
Even if distinctive features that might indicate a tornado are observed on radar, a tornado must be observed visually before a tornado warning is issued
There is a reduction in the number of Atlantic hurricanes during a major El Niño event.
If a hurricane remains over warm water of sufficient depth, it may survive for several weeks.
Lows that develop over polar waters during the winter exhibit many of the characteristics of a hurricane and are sometimes referred to as Arctic hurricanes.
Despite there being many differences in structure, if a weakening hurricane links up with an upper-level trough it may actually become a mid-latitude cyclone.
Statistical models that compare a present hurricane with similar storms in the past have been very successfully used to forecast changes in a hurricane's intensity.
Most hurricanes develop in warm tropical waters at the Equator even though the Coriolis force is zero there.
The terms typhoon and cyclone refer to the initial weaker stages in the development of a hurricane.
The name of a particular memorable or damaging hurricane will not be used again for a period of at least ten years
Most hurricanes have fronts.
Hurricane development is more likely when the trade wind inversion is well developed.