exam 3

Question 1

Definition of air mass & source region? What distance can an air mass cover?

Answer 1

air masses is large body of air whose properties of temp. and humidity are similar in any horizontal direction at any latitude. Can cover more than million square. Usually dominated by high surface pressure.

Question 2

What do continental polar & arctic (cP & cA) air masses typically form?

Answer 2

Alaska, Canada, and Arctic

Question 3

What are the characteristics of Matimine Polar (mP) air mass?

Answer 3

Air is warmer at the surface than aloft & water vapor produces rain & snow & cumulus clouds over the ocean.

Question 4

what are the characteristics of the Maritime tropical (mT) air mass? What is another name for it?

Answer 4

Pineapple Express, brings warm, moist air to the west coast that produces heavy precipitation.

Question 5

What is the definition of a front?

Answer 5

Transition zones between two air masses of different densities

Question 6

What are the characteristics of cold front?

Answer 6

zones where cold, dry polar air replaces warm, moist unstable subtropical air.

Question 7

what is a dry line? What does is separate?

Answer 7

boundaries where there are steep horizontal changes in moisture & separate moist from dry air.

Question 8

What is an occluded front?

Answer 8

are created when a cold front overtakes a warm front.

Question 9

what is the polar front? know the stages of development for the polar front & their order know how to draw the stage

Answer 9

Polar front is a semicontinuous global boundary spending cold polar from warm subtropical air. The stages are 1) cold & warm air flow in opposite direction along a stationary front. 2) frontal wave develops on the front 3) open wave & precipitin develop 4) mature cyclone develops 5) system become occluded; stone become intense triple point develop 6) storm dissipates

Question 10

what is cyclongenesis?

Answer 10

development is strengthening of a mid-latitude cyclone

Question 11

what is Rossby wave?

Answer 11

is long-wave ( several thousand of km wavelength)

Question 12

how does baroclinic instability occur? how doe shortwaves interact w/ long-waves in the upper atmosphere?

Answer 12

when shortwave disturb parallel air flow between Rossby wave & isotherms. It creates baroclinic instability.

Question 13

what is a cold belt? a warm belt? a dry belt?

Answer 13

cold belt: precipitation evaporates into cold air- air rises upward, turns counterclockwise
Warm belt: originate at the surface, rise along the warm front & produces precipitation.
Dry belt: form in cold, dry upper troposphere being clear, dry weather, & dry slots.

Question 14

what is the definition of vorticity? what type of air flow is involved in positive voracity? negative vorticity?

Answer 14

meteorologist seek regions of divergence on upper- level crates to accurately predict developing storms. Positive vorticity: cyclonic (counterclockwise) spin. Negative vorticity: anticyclonic (clockwise) spin.

Question 15

what is the definition of vorticity? what type of air flow is involved in positive vorticity? negative vorticity?

Answer 15

precipitin produce strong winds & heavy snow; mostly in winter. Polar lows are known for develop over polar water behind the main polar front.

Question 16

what do forecaster have access to?

Answer 16

maps, charts, counting, sounding, visible & infrared satellite images, copper radar, and atmosphere models.

Question 17

how many land-based surface & upper air data starters are there?

Answer 17

there are more than 10,000 & upper are data stations are there

Question 18

what information can satellites receive?

Answer 18

receive lighting, sea surface temp & smoke from forest fires

Question 19

what is the topper radar?

Answer 19

provides round- the- clock information on rain, snow, sleet & hail. They provide warning of destructive windstorms & tornados.

Question 20

what does WMO stand for? NWS?

Answer 20

WMO: world meteorological organization
NWS: the national weather service

Question 21

what are the difference forecasting tools? what does each of them show?

Answer 21

1) metograms- shows changing variables over time at a station.
2) sounding- shows 2-D vertical profits of temp dew point & winds
3) thickness charts- shows/assits in analyzing temp at different stations

Question 22

what is prog?

Answer 22

(prognostic chart) displays the atmosphere at a specified future time

Question 23

what are the rules of thumb for determining the movement of weather system?

Answer 23

1) midlatitudes cyclones storms & fronts move in the same direction & speed as for the past 6hrs
2) low pressure areas does in a direction that parallel isobar’s of warm air.
3) low move forward the greater pressure drop.
4) high moves forward the greater pressure rise
5) surface pressure system movie the same direction as the wind at 5,500m

Question 24

what is an isallobar?

Answer 24

lines of equal pressure change on weather maps indicates regions of falling or rising pressure

Question 25

know the forcing mechanisms fr thunderstorm

Answer 25

random turbulent eddies, equal surface heating, terrain effects & uplift along mountains, diverging upper-level winds: covering surface winds & rising air. & warm air and warm air rising along a frontal zone.

Question 26

know the difference type of thunderstorms & their characteristics

Answer 26

serve- produces hail with a diameter of at least 1 and surface wind gusts of at least 50 knots or a tornado
scattered- form in warm; humid air masses away from fronts
multicell & suspended- intense rotating storm which produce serve winds, hail, floods, and tornado

Question 27

what are the stages of ordinary cell thunderstorm development?

Answer 27

cumulus stage, mature stage, dissipating stage

Question 28

what are the characteristics of a microburst? what kinds of winds can it produce?

Answer 28

a downbeat w/ winds that only extend 4 km or less can produce winds 100 knots (115 mil/hr)

Question 29

what are squall-line thunderstorm?

Answer 29

multicell thunderstorm forming a line of thunderstorms

Question 30

what is a derecho?

Answer 30

straight line winds gusting to move than 58 mil/hr for at least 250 mi

Question 31

what are the various configuration of a mesoscale convective system(McSs) ?

Answer 31

elongated squall lines, circular mesoscale convective vortices an mesoscale convefive complex.

Question 32

what is a supercell thunderstorm?

Answer 32

intense, long lasting thunderstorm w/ a single violently roaring updraft

Question 33

what are the difference type of supercell thunderstorm? what are the characteristics of each?

Answer 33

mesocyclones: a roasting air column usually 5-10 km across updraft creates a rain-free zone
wall cloud: a rotating cloud descending from the base of the storms base

Question 34

what is a tornado is? what is a funnel cloud?

Answer 34

feature a rapidly rotating column of air extending down form a cumuliform cloud with circulation reaching the ground.
funnel cloud: a tornado that is forming but whose circulation has not reached the ground.

Question 35

know the tornado life cycle & the order of each stage

Answer 35

dust whirl; dust swirls upward
organizing; intensity increase and a downward funnel form
mature: funnel reaches maximum width and is almost vertical
shrinking: funnel decrease in width and tilt
decay shape: a tornado stretches into a rope shape

Question 36

what is a multi- vortex tornado?

Answer 36

contain smaller whirls called suction vortices

Question 37

the difference between a tornados watch and a tornado warning?

Answer 37

tornado watch is issued by the storm prediction center
tornado warning : issued by the NWS when a tornado is sighted

Question 38

in what kind of storms do tornadoes most often form?

Answer 38

thunderstorm (supercell thunderstorm)

Question 39

what does wind shear create a tornado in a supercell thunderstorm?

Answer 39

create rotation near the surface creating vortex tubes tilting upward

Question 40

how are winds displayed on a Doppler radar? what color represents what?

Answer 40

winds are displayed in color; winds moving toward the radar antenna are blue or green. winds moving away by red shades.

Question 41

what is the polarimetric radar? what does is measure?

Answer 41

also called dual- polarization radar; transmits both a horizontal & vertical radar pulse. Allows forecasters to distinguish between rain and hail.