Weather Flashcards
In which atmospheric layer does weather normally occur?
Troposphere
The stratosphere is characterized by smooth flying conditions and excellent ______.
Visibility
What is the standard sea level temperature in degrees Celsius (° C)?
15
With a pressure change of 1.0 in - Hg, how many feet will the altimeter reading change?
1000
If the air is colder than the standard atmosphere, the aircraft will be ______ than the altimeter indicates?
Lower
What is the initiating force for all winds?
Pressure Gradient Force
Low pressure results from ______ air.
ascending
The jet stream is the narrow band of strong winds found below the ______.
tropopause
A weak pressure gradient force would be indicated by a ______ isobar spacing?
wide
The forces that determine the wind direction in the atmosphere are weakened at the Earth’s surface by the force of ______.
friction
Below 2000 feet AGL, ______ reduces the speed of the wind.
friction
What type of clouds contain numerous hazards such as severe to extreme turbulence, hail, icing, andlightning?
Cumulonimbus
Three forms of precipitation are ______, ______, and ______.
drizzle, rain, frozen
The four methods of atmospheric lifting are convergence, frontal, thermal, and ______.
orographic
______ defines air with the same temperature as the surrounding air after being lifted.
neutrally stable
Air is ______ when it contains the maximum moisture possible for a given temperature.
saturated
Names of middle clouds contain the prefix ______.
alto-
Lifted air that is warmer than surrounding air continues to rise and indicates a(n) ______ condition.
unstable
What properties are used to locate and classify fronts?
Temperature, dew point, pressure, wind
What parameters of an air mass are generally uniform when measured across a horizontal plane?
Temperature and moisture
How will the winds shift during a cold front passage?
90 degrees, parallel ahead of the front and perpendicular behind it.
Squall lines generally develop where?
50 -300 miles ahead of the cold fron
The area that encompasses the weather located on either side of a front is called the ______.
frontal zone
Every front is located in a _______.
low-pressure trough
A line of violent thunderstorms that forms ahead of a cold front are known as ______.
squall line
How far ahead of awarm front can the associated cloud system reach?
50 to 300 miles
When encountering a stationary front, you can expect a ______° wind shift since surface winds tend to blow parallel on both sides of the front.
180
When flying through an occluded front, you can expect weather associated with ______ fronts.
both cold and warm
The most severe weather with respect to anoccluded front is generally located ______ NM south to______ NM north of the frontal intersection.
100; 300
A(n) ______ front usually has no clouds or precipitation. (B/4/3)
inactive
What kind of frontal system is depicted by a purple line with both cold and warm front symbols on the same side of the line?
Occluded front
Which frontal system has a steeper slope?
A cold front
How does the wind normally shift with the passage of a warm front?
90 degrees
What type of weather is usually associated with a stationary front?
Weather similar to a warm front, but usually less intense
What are the four levels of turbulence intensity?
Light, Moderate, Severe, Extreme
What are the four classifications of turbulence?
Thermal, Mechanical, Frontal, Windshear
What type of frontal activity is likely to produce the most turbulence?
Cold Front
What category of turbulence is characterized by large variations in airspeed and abrupt changes in attitude and altitude?
Severe
Turbulence occurring less than ⅓ of the time is described as ______.
Occasional
Moderate turbulence can extend as far as ______ miles downwind of a mountain wave.
300
What are the three types of wind shear turbulence?
Jet stream, Gusty winds, Temperature inversion
What type of icing is found in cumuliform clouds and unstable conditions?
Clear
What type front produces the most significant icing conditions?
Occluded
What are the greatest hazards associated with induction and compressor icing?
Engine flameout and FOD
What conditions are necessary for the formation of aircraft icing?
- visible moisture
- super cooled water droplets
- Free air temperature and aircraft skin temperature below freezing
What are the two types of engine icing?
Compressor and Induction
True or false? Induction icing requires visible moisture and sub-freezing temperatures.
False
True or false? When finding yourself in icing conditions, you can escape by flying into areas of colder temperatures.
True
At what intensity of icing is rate of accumulation a problem if encountered for an extended period of time?
Light
Define slant range visibility.
Distance on final approach when the runway environment is in sight
Define Prevailing visibility.
Greatest horizontal visibility through over 1/2 the horizon circle but does not need to be continuous
What is the minimum sky coverage constituting a ceiling?
5/8 or Broken (BKN)
True or false? Advection fog is dissipated by solar heating.
False
If an aircraft encounters an ash cloud in flight, what is the best procedure for the pilot to use to escape the cloud?
180° turn to escape
Total visibility over half the horizon circle or greater is ______.
Prevailing Visibility
______ is the distance that be seen directly upward from the ground into a surface-based obscuration.
Vertical Visibility (VV
Which type of fog produces a thicker, more persistent layer?
Advection Fog
Extra Credit:
What are the 5 types of Fog?
R - Radiation
A - Advection
I - Ice
S - Steam
U - Upslope
R - Radiation: stable nighttime conditions, radiation cools the ground, which causes a temperature inversion. In turn, moist air near the ground cools to its dew point forming radiation fog formation.
A - Advection: moist air moving over a colder surface
I - Ice: composed of ice crystals instead of water droplets and forms in extremely cold
S - Steam: in northern latitudes, steam fog forms when water vapor is added to air
that is much colder, then condenses into fog
U - Upslope: occurs when sloping terrain lifts air, cooling it adiabatically to
its dew point and saturation
What do roll and wall clouds indicate?
Low level wind shear and extreme turbulence
A ______ forms on the surface at the leading edge of an advancing thunderstorm.
Gust Front
Why do you want to fly over the top, at least 1000 feet per knots of wind speed at cloud top level, to void a thunderstorm?
avoid the turbulence and hail
Why do you want to penetrate the lower ⅓ of a thunderstorm?
below the freezing level to avoid icing
What combination of atmospheric conditions are necessary for the formation of a thunderstorm?
moisture, unstable air, lifting action
What effects can turbulence have on an aircraft?
changes in altitude and attitude, structural damage
What hazards are associated with lightning?
structural damage, damage to electronic equipment ignition of fuel vapors, pilot flash blindness
If a thunderstorm is approaching do not ______ or ______.
takeoff or land
Why do you want to penetrate a thunderstorm perpendicular?
minimize the time in the storm
What hazards to flight are associated with thunderstorms?
turbulence, hail, lightning, tornados, microbursts
Microbursts are an intense, highly localized downward atmospheric flow with velocities of ______ to over ______ feet per minute
2000 , 6000
What methods can be used to detect a microburst?
Virga, Vortex dust ring, rain showers, radar, pireps
How will the indicated airspeed change when flying through a microburst?
increase rapidly, then decrease rapidly
Using the METAR shown, what is the reported ceiling for KLUF?
METAR KLUF 2157Z 16009KT 10SM SCT015 BKN027 BKN200 04/M06 A2999 RMK SLP190
a. 1500 feet
b. 2700 feet
c. 20.000 feet
d. No ceiling reported
b. 2700 feet
Using the METAR shown, what is the temperature for KLUF?
METAR KLUF 2157Z 16009KT 10SM SCT015 BKN027 BKN200 04/M06 A2999 RMK SLP190
a. 4°C
b. 4° F
c. 6° C
d. 4° F
a. 4°C
Using the SPECI shown, what are the winds at KMIB?
SPECI KMIB 0123Z 01023G35 1/2SM R11/1200FT –BLSN SCT000 OVC005 RMK VIS3/8V5/8 BLSN SCT000 CIG 004V006
a. 00° at 4 to 6 knots
b. 120° at 10 knots, gusting to 23 Knots
c. 10° at 23 knots, gusting to 35 knots
d. Light and variable
c. 10° at 23 knots, gusting to 35 knots
Using the SPECI shown, what is the Runway Visual Range (RVR) at KMIB?
SPECI KMIB 0123Z 01023G35 1/2SM R11/1200FT -BLSN SCT000 OVC005 RMK VIS3/8V5/8 BLSN SCT000 CIG 004V006
a. 400 feet for Runway 06
b. 600 feet for Runway 04
c. 1/2 SM for Runway 11
d. 1200 feet for Runway 11
d. 1200 feet for Runway 11
What is the minimum sky coverage constituting a ceiling? (B/2/1)
a. 3/8 to 4/8
b. 4/8 to 5/8
c. 5/8 to 7/8
d. 8/8
5/8 to 7/8
Given the following observation sequence, what is the ceiling at KRND?
KRND 1356Z 18005KT 7SM SCT025 BKN050 OVC140 28/26 A3006
a. 500 feet
b. 2500 feet
c. 5000 feet
d. 14,000 feet
c. 5000 feet
Using the SPECI below, what is the most detailed visibility shown?
SPECI KMIB 0123Z 01023G35 1/2SM R11/1200FT -BLSN SCT000 OVC005 RMK VIS3/8V5/8 BLSN SCT000 CIG 004V006
a. ½ SM
b. 1100 to 1200 feet
c. 3/8 to 5/8 SM
d. Visibility is not reported.
c. 3/8 to 5/7 SM
Using the METAR shown, what is the dew point for KLUF?
METAR KLUF 2157Z 16009KT 10SM BKN027 BKN200 04/M06 A2999 RMK SLP190
a. 4° C
b. -4° C
c. 6° C
d. -6° C
d. -6° C
Using the METAR shown, what is the altimeter setting for KCBM?
METAR KCBM 291158Z AUTO 14004KT 10SM FEW080 20/18 A3001 RMK AO2 SLP163
a. 29.11
b. 29.92
c. 30.01
d. 30.11
c. 30.01
Using the METAR shown, what is the sea level pressure at KCBM?
METAR KCBM 291158Z AUTO 14004KT 10SM FEW080 20/18 A3001 RMK AO2 SLP163
a. 1016.3 mb
b. 916.3 mb
c. 1001.63 mb
d. 3011in Hg
a. 1016.3 mb
From the TAF shown, what is the worst forecast ceiling at KNSE for an ETA of 2000Z?
a. 100 feet
b. 800 feet
c. 1000 feet
d. 2500 feet
a. 2500 feet
Using the TAFs shown, what are the forecast winds at KNBG for an ETA of 0600Z?
a. 100° at 5 knots
b. 020° at 8 knots
c. 050° at 10 knots
d. Variable at 2 knots
b. 020° at 8 knots
Using the TAFs shown, what is the altimeter setting at KLFI for an ETA of 2000?
a. 2008 hg
b. 2993 hg
c. 3000 hg
d. No altimeter setting is reported.
c. 3000 hg
In the TAF shown, what is the entire forecast valid time period?
a. 0900 on the 9th to 0900 on the 10th
b. 0900 on the 26th to 0900 on the 27th
c.0900 on the 26th to 0900 on the 28th
d. 0400 on the 28th to 0400 on the 29th
b. 0900 on the 26th to 0900 on the 27th
In the TAF shown, what are the forecast winds at KNSE for an ETA of 1700?
a. 230° at 15KT, gusting to 25K
b. 280° at 4KT
c. 260° at 7KT
d. Calm
a. 230° at 15KT, gusting to 25K
Using the TAF shown, what would be the lowest visibility forecast with an ETA of 1500Z at KLCH?
a.4 statute miles in haze.
b.2 statute miles in thunderstorms and rain.
c.2 statute miles in mist.
d.5 statute miles in haze.
c. 2 statute miles in mist
Using the TAF shown, when is the lowest ceiling forecast for KSEA?
a. Between 0600Z and 1800Z on the 31st.
b. Between 2200Z on the 30thand 0600Z on the 31st.
c. Between 1800Z on the 30thand 1800Z on the 31st.
d. Between 1800Z and 2200Z on the 30th.
d. Between 1800Z and 2200Z on the 30th.
Weather Practice test
A decrease in temperature with increasing altitude indicates a ______ lapse rate.
Standard
An abrupt change in the rate of temperature decrease with increasing altitude can be found in the ______ layer.
Tropopause
True or false? All aircraft can fly in the stratosphere.
False
What are the typical flight conditions in the stratosphere?
Excellent visibility and smooth flying
True or false? Atmospheric pressure increases with altitude.
False
A constant temperature with increasing altitude is an example of a ______ lapse rate.
Isothermal
The altimeter setting is corrected for ______.
Sea Level Pressure
The altimeter is calibrated for a ______ lapse rate
Standard
If the air is warmer than the standard atmosphere, the aircraft will be ______ than the altimeter indicates.
Higher
With a pressure change of 1.0-Hg, howmany feet will the altimeter reading change?
1000
A single barb on a station model indicates ______ knots of wind.
10
True or false? The wind direction around a high is counterclockwise.
False
A strong pressure gradient force means a ______ wind speed.
Faster
High pressure results from ______ air.
Descending
A narrow band of strong winds found below the tropopause is called ______.
Jet Stream
What are the three states of moisture?
Solid, liquid, gas
______ clouds produce heavy steady precipitation.
Nimbostratus
What are the methods of lifting?
Thermal, Mechanical, Frontal, and Orographic
What are the three conditions of atmospheric stability?
stable, neutrally stable, and unstable
On a clear day, the radiation received from the sun will most likely produce ______ lifting.
Thermal
What is an air mass?
A large body of air with uniform temperature and moisture across a horizontal plane.
What properties are used to locate and classify fronts?
Temperature, dewpoint, pressure, and wind
What parameters of an air mass are generally uniform when measured across a horizontal plane?
temperature and moisture
Cold fronts are caused by overtaking cold air being more ______ than warm air.
dense
How will the winds shift during a cold front passage?
90°
A line of severe thunderstorms is known as a(n) ______.
Squall line
What are the characteristics of a squall line?
Line of severe thunderstorm
What are possible aviation hazards associated with a squall line?
Turbulence, hail. lightning, and microbursts
With a warm front, does weather occur ahead of or behind the surface front?
Ahead
What type of wind shift will you expect to find when encountering a stationary front?
180°
An occluded front is formed when a ______ front overtakes a ______ front.
Cold , Warm
True or false? A wind shift and temperature change do not occur during the passage of an inactive front.
False
What are the turbulence intensity classifications?
Light, Moderate, Severe, Extreme
During ______ you will experience large abrupt changes in altitude and/or attitude.
Severe turbulence
Thermal turbulence is also known as ______.
Convective turbulence
Frontal turbulence is caused by warm air lifted by a ______.
Cold Front
True or false? A wind shear is always caused by a sudden change in wind speed or direction over a short distance vertically.
False
What are the requirements for icing?
Visible moisture, supercooled water droplets, air temp and aircraft skin temp below freezing
What are the types of icing?
Clear, Rime, Mixed and Frost
What type of front is associated with rime icing?
Warm front
Wha ttype of front is associated with mixed icing?
Occluded front
To avoid icing, why would climbing to a colder temperature be a consideration?
ice crystals will not stick to the aircraft
How is visibility expressed?
Statute miles, feet or meters
What is Runway Visual Range (RVR)?
Horizontal visibility down the runway from the approach end.
What are the types of obscuring phenomena?
rain, snow, mist, dust, haze etc.
What is sky coverage?
The amount of sky covered by clouds, reported in eighths. Includes coverage at the lowest cloud layer plus the additional coverage present at all successively higher cloud layers.
What is a ceiling?
Height above the ground (AGL of the lowest broken or overcast clouds, or the vertical visibility into a ground based total obscuration.
What are the two types of fog?
Radiation and Advection
What are some indications of flying into volcanic ash?
Torching, St Elmo’s Fire, Bright glow in the engine inlets
What are some hazards of flying into volcanic ash?
Engine flameouts, Pitted windscreens, sandblasting of the leading edges
What aviation hazards are associated with thunderstorms?
Turbulence, hail, icing, lightning, wind shear, tornados
What is the cause of electrostatic discharge?
Results from positive and negative charge, from water and ice passing in up and down drafts
What are some aviation hazards associated with lightning?
a. Static charge builds up in the aircraft while in the clouds.
b. Can strike aircraft flying in the clear.
c. Structural damage is possible.
d. Catastrophic fuel ignition is possible.
e. Pilots can experience flash blindness.
f. Static buildup sometimes released through St. Elmo’s fire.
What are some visual indications of possible microburst activity?
Virga, Localized blowing dust, Shaft of rain which diverges closer to the ground, Severe thunderstorms
What is the sequence of events a pilot will encounter when flying through a microburst?
Increasing headwind and indicated airspeed then Tailwind and decreasing indicated airspeed
Should you reduce power when landing during a microburst?
No. Reducing power wastes valuable time to get the aircraft away from the ground before entering outflow.
What are the best choices, in order of priority, for avoiding the penetration of a thunderstorm?
Around, over, under
What is the most accurate means of tracking thunderstorms?
NEXRAD (Next Generation Radar)
Using the SPECI shown, what is the prevailing visibility reported at KNFB?
KNFB SPECI 0123Z 01023Z 01023G35 1/2SM R36R/12OO FT -BLSN SCT000 OVC0005 RMK VIS 3/8V5/8 BLSN SCT000 CIG 004V006
½ SM
In the METAR shown, what is the reported ceiling at KSEA?
METAR KSEA 311256Z 03011KT 10SM SCT002 BKN007 OVC025 08/07 A2997 RMK AO2 SLP149
700 Feet
In the METAR shown, what are the winds at KSEA?METAR KSEA 311256Z 03011KT 10SM SCT002 BKN007 OVC025 08/07 A2997 RMK AO2 SLP149
030° at 11 knots
In the METAR shown, what is the dew point at KSLC?METAR KSLC 161156Z 17008KT 10SM BKN250 26/11 A2997 RMK A02 SLP080
11° C
Using the TAF shown, what winds would you expect for an ETA of 1800Z at KTIK?
150°at 10 knots
Using the TAF shown, what is the forecast ceiling for an ETA of 2300Z at KDOV?
Broken at 700 feet
Using the TAF shown, what would be the forecast visibility with an ETA of 1600Z at KLCH?
4 SM in haze
Using the TAF shown, what is the forecast ceiling foran ETS of 0200Z at KSEA?
2500 feet overcast
A strong pressure gradient force mean a ______ wind speed.
Faster
A narrow bandof strong winds found below the tropopause is the ______.
Jet stream
What are the atmospheric cycles?
Evaporation, condensation and precipitation
The ______ is used to determine air mass boundary.
Dewpoint
True or false? A squall line does not contain any potential hazard to aviation.
False
Alternating cold and warm front symbols on opposite sides of the frontal line indicates a/an ______.
Stationary Front
A definite strain against seat belts and shoulder straps would indicate ______ turbulence.
Moderate
What are the types of wind shear turbulence?
Jet stream, gusty winds and temperature inversion
What are the possible effects of icing?
aerodynamic effects, performance effects, pitot-static system faulty indications
What are the types of fog?
Radiation and advection
What type of clouds indicate the presence of low level wind shear and extreme turbulence?
Roll clouds and wall clouds
A shaft of rain which diverges closer to the ground is an indication of a ______.
Microburst
What are the three requirements for thunderstorm development?
Moisture, unstable air and some lifting action.
What is the preferred method to avoid an isolated thunderstorm?
Circumnavigate an isolated thunderstorm.
What is a Terminal Aerodrome Forecast (TAF)?
Airport forecast for specific period, Used to determine VFR or IFR flight plan requirements
What effects can turbulence have on an aircraft?
a. Can cause change in altitude
b. Can cause structural damage
c. Extra stress of the airframe
d. Effect depends on the severity of the turbulence and speed of the aircraft.
The information displayed on the Surface Analysis Chart is observed weather, meaning that the chart represents past history, and is not a forecast.
a. True
b. False
True
Barometric pressure lines (isobars) are drawn at ______-millibar intervals
a. 2
b. 4
c. 10
d. 50
4
The valid time of a Surface Analysis chart is given in local time at the top right.
a. True
b. False
false
METARs are scheduled observations taken between ______ minutes past the hour.
a. 10-15
b. 25-30
c. 40-45
d. 55-59
55-59
NEXRAD displays what is referred to as a “hook echo” that is considered indicative of a ______.
a. tornado
b. hurricane
c. lightning strike
d. pirate attack
tornado
______ satellite imagery displays clouds and the Earth reflecting sunlight back to the satellite sensors.
a. Infrared
b. METAR
c. NEXRAD
d. Visible
Visible
A flag on a wind barb on a Winds-Aloft Prog Chart represents ______ knots of wind.
a. 10
b. 25
c. 50
d. 100
50
On Winds Aloft Prognostic Charts, all temperatures are negative above ______ feet.
a. 10,000
b. 18,000
c. 24,000
d. 36,000
24,000
A direction of ______ in a Winds-Aloft Forecast indicates a variable wind direction.
a. 00
b. 99
c. 900
d. 999
99
Which one of the following lists the conditions for issuing a WW? (C/1/1)
a. Turbulence and hail
b. Hail and lightning
c. Tornadoes and severe thunderstorms
d. Icing and gusty surface winds
Tornadoes and severe thunderstorms
The first issuance of any non-convective SIGMET will always be identified as an ______.
a. Urgent SIGMET (UWS)
b. Priority SIGMET (PWS)
c. Initial SIGMET (IWS)
d .Leading SIGMENT (LWS)
Urgent SIGMET (UWS)
For Convective SIGMETs, a line of thunderstorms is defined as being at least ______ miles long with thunderstorms affecting at least ______ percent of its length.
a. 50; 50
b. 60; 40
c. 70; 30
d. 100; 75
60; 40
An AIRMET ______ is issued for widespread IFR conditions (ceilings less than 1000 feet and/or visibility less than 3 miles) affecting over 50% of the area or for extensive mountain obscuration.
a. Tango
b. Zulu
c. Sierra
d. Bravo
Sierra
Air traffic facilities are required to solicit PIREPs whenever ceilings are at or below ______ feet and visibility is at or below ______ mile(s). (C/2/4)
a. 1000; 1
b. 3000; 3
c. 5000; 5
d. 10,000; 10
5000; 5
NEXRAD is capable of displaying areas of ______.
a. tornadoes
b. hail
c. wind shear
d. all of the above
all of the above
In a textual Winds-Aloft chart, if winds are called “light and variable,” the code ______ will be listed.
a. “C”
b. “9900”
c. “L”
d. “00”
b. “9900”
Convective SIGMETs (WST) are issued only for thunderstorms and related convective phenomena over the conterminous US.
a. True
b. False
True
If you’re unable to pass a PIREP while in the air, you should report to ______ upon landing.
a. the nearest FSS
b. Base Operations
c. squadron operations
d. your flight commander
the nearest FSS
Clouds will usually show up white on a visible satellite image since clouds are much ______ than most of the earth.
a. more dense
b. more reflective
c. warmer
d. lighter
warmer
Wind information is never forecast for altitudes within ______ feet of the surface.
a. 500
b. 1500
c. 5000
d. 10,000
1500
On a Surface Analysis Chart, the pressure systems mentioned are outlined by isobars drawn at______-millibar intervals.
a. 2
b. 4
c. 8
d. 10
4
On a Winds-Aloft forecast, temperature information is never forecast within ______ feet of the surface.
a. 1000
b. 2500
c. 5000
d. 10,000
2500
Aviation Severe Weather Watch Bulletins can be issued for severe thunderstorms, defined by frequent lightning and ______ knots of wind or greater or ______ diameter hail or larger.
a. 30; ½ inch
b. 50; ¾ inch
c. 50; 1 inch
d. 75; ½ inch
50; ¾ inch
An AIRMET valid period expiration time is ______ hours after the scheduled “valid beginning” time.
a. 2
b. 6
c. 12
d.24
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