38 terms


Modern computer forecasting models have increasingly smaller grid spacing. This presents which of the following problems?
much more computations are needed
Lines connecting points of equal pressure change are called:
In a severe thunderstorm, hail may:
fall from the base of the anvil
fall from the bottom of the cloud
be tossed out the side of the cloud
A line of thunderstorms that forms ahead of an advancing cold front is called a:
squall line
Most squall line thunder storms form:
in advance of a cold front
Thunderstorms that move to the right of the winds aloft tend to:
cut off the supply of humid air to thunderstorms to the north of them
Many flash floods, including those that occurred in Rapid City, South Dakota, and in Colorado's Big Thompson Canyon, are the result of thunderstorms that:
move slowly
The region in the United States with the greatest annual frequency of hailstones is:
the Midwest
The greatest annual number of thunderstorms in the United States occurs in:
In the United States, dryline thunderstorms are most common
In the great plains
A second surge of electrons that proceeds from the base of a cloud toward the ground during cloud-to-ground lightning is called a:
dart leader
An important principle in the electrification of a cumulonimbus cloud is that:
there is a net transfer of positive ions from a warmer object to a colder object
You a generally safe inside an automobile during a lighting storm because:
the metal car body will carry the lightning current around the passengers inside
A funnel cloud is composed primarily of:
ice crystals
The small, rapidly rotating whirls that sometimes occur within a large tornado are called:
suction vortices
A funnel cloud or tornado may develop from this rotating cloud that extends beneath a severe thunderstorm.
wall cloud
The funnel cloud characteristic of a tornado is principally formed by:
condensation of water vapor in air drawn into the low pressure core of the tornado
Which of the following factors is most important in determining the strength of a tornado?
central pressure
If a tornado is rotating in a counterclockwise direction and moving toward the northeast, the strongest winds will be on its __________ side.
Different tornadoes spawned by the same thunderstorm are said to occur:
in families
Which of the following regions would you expect to have the most tornadoes in the winter?
southern Gulf States
Tornadoes are usually observed:
In front of cold fronts
In an eastward moving thunderstorm, the most likely place for a tornado to develop is in the __________ part of the storm.
In a region where severe thunderstorms with tornadoes are forming, one would not expect to observe:
a strong ridge of high pressure over the region
Which below is the best indication that a severe thunderstorm is about to produce a tornado?
a wall cloud
The Fujita scale pertains to:
the strength of a tornado
About three-fourths of all tornadoes fall into which of the following categories on the Fujita scale?
F0 or F1
Damage to structures inflicted by tornadoes can be caused by:
flying debris
the tornadoes high winds
the drop in air pressure as a tornado moves overhead
the drop in air pressure above a roof as high winds blow over it
After a tornado is spotted:
a tornado warning is issued
A hook-shaped echo on a radar screen often indicates:
the possible presence of a tornado-producing thunderstorm
The instrument that measures the speed at which precipitation is moving toward or away from an observer is:
Dopplar radar
A Doppler radar determines precipitation __________ by measuring changes in the __________ of the reflected radiowave.
Velocity, frequency
On a Doppler radar screen, a tornado vortex signature (TVS) appears as:
A region of rapidly changing wind speeds
Most waterspouts:
Have rotating winds of less that 45 mph
Which is not a characteristic of a "fair weather" waterspout?
Generally indicate stable atmospheric conditions
A tornado-like event that forms over water is a:
Most waterspouts would fall into which category of the Fujita scale?
Light flashes darting upward from the tops of thunderstorms are called
sprites and blue jets