NWA Test Flashcards
What “mb” chart is used to determine short waves/long waves (ridges, troughs)?
500 MB
What “mb” chart to find absolute vorticity?
500 MB
Moderate to strong low pressure systems will be driven by the flow at this “mb” level.
500 MB
What “mb” level is at the top of the troposphere and in the lower stratosphere?
300 MB, 250 MB and 200 MB charts
What “mb” level are the jetstream winds and jetstreaks found at?
300 MB, 200MB
What “mb” level for confluence and difluence?
300 MB, 250 MB, 200 MB
What has the highest albedo?
- asphalt
- ocean
- forests
- clear skies
- clouds
clouds (snow has the whitest albedo)
If there are cold air “backing” winds involved with a low pressure system, where will the strongest winds be?
- center
- south
- east
- northwest
Northwest
What kind of advection happens aloft in an ice storm?
- Weak CAA
- Strong CAA
- Weak WAA
- Strong WAA
Weak WAA
What is evidence of an EF0 tornado?
- Catastrophic
- No damage
- Little damage
Little damage
What does the Saffir Simpson scale measure?
1 to 5 rating based on a hurricane’s sustained wind speed
In which direction do a hurricane’s winds go?
- outward only
- inward only
- inward at the surface, outward aloft
- outward at the surface, inward aloft
inward at the surface, outward aloft
What is an example of a short term model?
NAM = 84 hours
What is an example of a long term model?
GFS = 16 days
What does a NPN profile measure and how often?
wind / 15-60 minutes
What does ASOS not report?
- dewpoint
- temperature
- wind
- precip type
- cloud type
cloud type
ASOS tells you everything except…
- precip type
- cloud height
- temp
- dew point
- wind
- none of the above
None of the above
When is hail the most common in the US?
June to August
Where is lightning most common?
Florida
This “mb” chart includes the low-level jet and is useful in identifying frontal boundaries and the rain/snow line?
850 mb
This “mb” chart intersects clouds and weak low pressure systems will be driven at this level and dry intrusions at this level are a precursor to severe weather.
700 mb
What does MOS “not” directly account for?
- Seasons
- Albedo
- Cloud Type
Seasons
What does not directly impact evaporation?
- Strong winds
- Radiation
- Dewpoint
- Relative Humidity
- Isobaric pressure
Isobaric pressure
What is the bright white on water vapor?
higher amounts of moisture
T/F Geostrophic winds move parallel to wind contours.
True
Geostrophic winds move _________ to height lines.
parallel
Winds move towards ______ pressure and are turned because of _______.
low, coriolis
Where would the strongest storm surge be in a hurricane?
- Left of the eye
- Behind the eye
- Right of the eye
- Right of the rear flank downdraft
- Left of the rear flank downdraft
Right side of the eye
where would the strongest storm surge be in a hurricane?
- Left of the eye
- Behind the eye
- Right of the eye
- Right of the rear flank downdraft
- left of the rear flank downdraft
Right of the eye
Do winds generally move across isobars, parallel to or not related to them?
Roughly parallel to isobars
How do infared satellites pick up their information?
through thermal radiation
In the early start of hurricane season, where do hurricanes normally form?
Gulf of Mexico, Bahamas and West Caribbean
What does clear air mode get?
reflectivity and velocity
This radar is used on a sunny day so it only scans the lowest levels of the atmosphere
Uses: Dry wx, very light precipitation, insects, birds, fronts
How do you identify a mesocyclone?
velocity
What is VADS information? (Velocity Azimuth Display)
radar that shows the average horizontal winds on a time versus height chart
How do you tell the direction and speed of a thunderstorm?
looping reflectivity
What chart gives you information on the weather that we are seeing and experiencing?
surface chart
What “mb” chart is the best to assess pure thermal advection?
850 MB
What “mb” chart to indicate relative humidity?
700 MB
How high is the 500 MB level (in feet)?
16,000 - 20,000’
How high is the 500 MB level (in meters)?
around 5,000 - 6,000 meters
How high is the 850 MB level (in feet?)
3,800’ - 5200’
How high is the 850 MB level (in meters)?
1170 - 1590 meters
How many miles is the 200 MB on average?
7.4 miles
How many feet up is the 200 MB level on average?
39,000’
How many miles up is the 250 MB level on average?
6.6 miles
How many feet up is the 250 MB level on average?
35,000’
How many miles up is the 300 MB level on average?
5.7 miles
How many feet up is the 300 MB level on average?
30,000’
How many miles up is the 500 mb on average?
3.4 miles
How many miles up is the 700 mb level on average?
around 2 miles
How many feet up is the 700 mb level on average?
10,000’
How many miles up is the 850 mb on average?
around 1 mile up
How many feet up is the 850 mb on average?
5,000’
What’s the most accurate forecast?
12 hours out
Most accurate numerical modes go out:
- 12
- 36
- 48
- 72 hours
12 hours
What angle is the local solar noon?
- 23.5 N
- 23.5S
- 0 degrees
- depends on latitude
- depends on longitude
Depends on latitude
This is the day every point on earth will have 12 hours of daylight and 12 hours of darkness.
Equinox
On the equinox, the earth’s tilt is perfectly perpendicular to the sun’s radiation, the from the sun’s perspective the earth is tilted neither toward or away from the sun. At the equator, the sun will be directly overhead at ______ on the equinox.
Solar noon
What is subrefraction?
When there’s less bending than normal causes radar to overshoot objects
What is vertically integrated liquid?
Amount of liquid water that the radar detects in a column of the atmosphere for an area of precipitation. High values are associated with heavy rain or hail
What is Vertically Integrated Liquid based off of?
Based on radar returns
When there’s divergence aloft, what is below?
convergence
What is happening aloft of a cold core low?
more intense circulation
In the northern and southern hemispheres, the jet stream comes form the ______ (north, south or west) at _______ (50 MPH or 100 MPH)
west, 100 MPH
What are a hurricane strength’s winds and gale force winds?
Hurricane: 74 MPH
Gale: 39 MPH
What is not a mid-Atlantic state:
- Delaware
- Maryland
- New Joersey
- Connecticut
Connecticut
The earth emits _______ (longwave or shortwave) radiation which is (visible or infared)
longwave, infared
How often is the NPN profiler data available?
15-60 mins
Order of cloud types in a MLC (mid-latitude cyclone) (from first to last)
- cirrus
- cirrostratus
- altostratus
- nimbostratus
- cumulus
- cumulonimbus
Behind front:
- post-frontal status
What is not an MCS?
Supercells
What season is the Azores/Bermuda high the strongest (summer/winter) and what impacts it has on the Eastern US (dry/humid)?
summer, humid
How is the strength of the tornado determined?
- wind only
- damages only
- wind and damages
damages
IF a south wind becomes westerly, is it veering or backing? Also, where would the low pressure be?
veering / north
Where is the jetstream in the winter ?
closer to 300 MB
Where is the jetstream in the summer?
closer to 200 mb
If lightning is observed, with thunder heard 10 seconds later, the storm producing the flash is _________.
2 miles
number of seconds between lightning and thunder / 5 - answer
In non-mountainous regions, one inch of liquid-equivalent precip on average results in approximately ____ inch(es) of snow at most locations for surface temp between 28-32 degrees.
10 inches
10 to 1 ratio
The sun’s rays are perpendicular to the earth’s axis at ____ degrees latitude during the _______.
0, vernal equinox
The earth rotates on a tilted axis of ____ degrees.
23.5
Severe convective wx is favored ahead of or behind a cold front?
ahead of a cold front
radiation fog over a large region is often associated with __________.
radiational cooling and HP
Ice storms are most common ________.
Ahead of warm fronts
Wind flow around a low pressure system in the Northern Hemisphere is ________.
inward and counterclockwise
Precipitation, as depicted on radar imagery does not exhibit ______.
an expanding circular formation with a “clear” center
The appearance of rain and snow on the WSR-88D base reflectivity, when occurring simultaneously is _______.
very similar
What is it called when the radar receives the pulse of energy back at the wrong time and incorrectly detects the distance and plots it in the wrong location?
Range folding
GenMet Data used input for numerical wx prediction models does NOT include________.
previous model output
How often does a radar need to scan a gauge in one hour?
Ideally needs a scan every 2.5 mins.
Visible satellite measures ________.
light reflected back
Infared satellite measures _________.
temperature
If something appears bright on visible satellite ______.
It is thick
If something is bright on infared, it is ________.
cold / high cloud tops
If something is darker on infared, it is ________.
warm / low cloud tops
Visible/Infared satellite only works in the daytime.
Visible
In a midwest MLC, what kind of air mass comes behind a cold front?
cP
In a midwest MLC, what kind of air mass comes in front of a cold front?
mT
In a midwest MLC, what kind of air mass comes behind a warm front?
mT
In a midwest MLC, what kind of air mass comes ahead of a warm front?
cP
What is an NPN?
Noaa Profiler Network
Back in the 90s and early 2000s
put them in the midwest / measured winds
6 min samples of the winds / so every hour
shut it down because of money
When there’s divergence aloft, what is below?
convergence
How do bodies of water impact climate?
Bodies of water take longer to heat up. Coastal communities tend to be warmer during winter and cooler during the summer.
How does elevation impact climate?
The higher up you go, the colder it gets because there is less air
How does latitude impact climate?
The higher up you go, the colder it gets because those areas receive less sunlight
What is the average planetary boundary layer in feet?
3,000 feet
What is the average planetary boundary layer in meters?
1000 meters
Is severe weather likely ahead of a cold front or behind it?
ahead
A mesocyclone is sometimes associated with a ________.
tornado
True or False: a tornado can rotate either counterclockwise or clockwise
true
counterclockwise in Northern Hemisphere
counterclockwise in Southern Hemisphere
According to the NWS, wind damage is expected when convective gusts reach or exceed ________.
58 MPH
A gust front results from _______.
thunderstorm downdraft
Although water vapor counts for _____ percent of the atmosphere by carbon dioxide ____ percent, both represent very important green house gases.
less than 1, less than 1
The ozone layer is found within the ______.
stratosphere
The polar jet is caused by _________ and is typically found ________.
thermal and momentum gradients
at the pole
During the warm season, the daytime planetary boundary layer is hydrostatic due to _____ effects.
unstable, thermal
The moist adiabatic lapse rate is approximately
6 degrees per every 1000 meters
When the temperature within the troposphere decreases more rapidly with height, the atmosphere is said to be ______.
unstable
The albedo of freshly fallen snow is _____ than the albedo of grassy surfaces.
much larger
The absorption of solar radiation by a surface is not a function of __________.
atmospheric pressure
The reduction in visibility due to haze results from ________.
scattering
water vapor in the atmosphere is typically largest in/at the
tropics (equator)
water vapor in the atmosphere is typically smallest at the _______.
poles
Hydrostatic balance is said to exist when two primary vertical forces are in balance. What forces are these?
gravity and vertical pressure gradient
When looking down the pressure gradient, coriolis deflection is to ______ in the southern hemisphere and to the _______ in the northern hemisphere.
left, right
Friction effects may change an air flow’s _____.
speed and direction
Surface divergence occurs within ______ pressure systems, which is generally a result in _______ weather.
high, fair weather
Upper level convergence implies _____ vertical motion and the development of surface _______ pressure.
downward, high
A strongly developing low pressure system is not characterized by which of the following conditions?s
Rising pressure
A high pressure center is not typically characterized by which of the following conditions?
strong winds
Which air mass may originate in the contiguous US?
cP
In the devleoping stages of an extratropical cyclone (mid lat cyclone) clouds and precip typically form _______.
closely ahead and behind fronts
A north to south flow of air is considered to be ______.
meridonial
The primitive equations used in numerical weather prediction models are based on ________.
newton’s law of motion
Visible imagery depicts clouds based on the _____ of shortwave radiation.
reflection
Dark spots or regions on a water vapor imagery generally indicate ________.
subsidence
GOES geostationary satellites ______ at all times.
view the same region
For a typical visible satellite image during the cold season over the US, warm fronts will most often be found ________.
in the middle of a cloud mass
When a lighter grey shading appears over land as compared to the ocean (on IR) it means that _______.
the land is cooler than the water
When considering radar, the term “target” is used to reference to _______.
precipitation
The rate of motion of precipitation returns on radar is based upon ___________.
The distance traveled by echoes over time
Positive and negative radial velocities that exist “gate to gate” (side by side) on a radar indicate _________.
rotation
When observing a thunderstorm cell with another directly behind it, the c-band (3-) will _____.
see the more distant cell to some extent
Radar range for determining reflectivity is not limited by ________.
heavy rainfall
Typical radar systems transmit signals with wavelengths of _____________.
1-10 cm
Clear air mode is “more/less” sensitive than precipitation mode.
More sensitive than precipitation mode
Range folding usually occurs within a distance of about _____ downrange from the antenna.
more than 50 miles
A bright band on the radar is often indicative of ______.
change in precipitation
The intensity level of precipitation on radar is represented by what?
expressed by dbz
Ground clutter can often by identified through ______.
looping the radar
A VAD wind profile provides _______.
a time plot of wind direction and speed
Super refraction causes a radar beam to be ______ .
bent more
T/F: When there is a heat wave in the SW US, there’s a low at the surface and high aloft.
False
ASOS are used for ______.
Most major airports
Isentropic analysis is primarily used to ______.
assess vertical motions
Ground based profiler primarily measures vertical________ profiles.
wind
In the Northern Hemisphere, the earth is closest to the sun in ___________.
January
The sun’s noontime angle of incidence is larger/smaller during the summer?
smaller
The rain/snow ratio may be as large as ________
30:1
For every second between lightning flash and the audible sound of the thunder producing the discharge is approx ____ away.
5 seconds per a mile
Flash flooding is most common in the U.S. during _______.
April, July and August
