JX Weather (SG) Flashcards
Weather should be studied and learned….
systematically and thoughtfully to accrue lifelong knowledge and as if my life will depend on it.
With a pressure change of 1.0 inHg, 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
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
What is the standard temperature lapse rate of the atmosphere in °Celsius per 1000 feet?
2.0
The average weight of air on a square inch of the Earth’s surface at sea level under standard conditions is
__________ pounds.
14.7 (SG says 14.7, answer key says 15.1)
Standard sea level pressure is 1013.2 mb or __________ inHg.
29.92
The height of an aircraft above the ground is known as __________ altitude
Absolute (SG says absolute, Answer key says pressure
For every 11 °C the temperature varies from the standard, there will be a __________% altimeter error.
4
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 half barb on a station model on a Winds-Aloft chart is equal to __________ knots.
5
On a Surface Analysis Chart, the pressure systems mentioned are outlined by isobars drawn at __________-
millibar intervals.
4
A strong pressure gradient force means a __________ wind speed.
faster
Jet Stream wind speeds average about __________ knots but can reach speeds in excess of __________ knots.
100 – 150; 250
Wind that is formed from denser air that flows downhill is called a
mountain wind.
What types of clouds contain numerous hazards such as severe to extreme turbulence, hail, icing, and lightning?
Cumulonimbus
Three forms of precipitation are __________, __________, and __________.
snow; hail; ice
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.
Stable (SG says stable, Answer key says unstable)
Air is __________ when it contains the maximum moisture possible for a given temperature.
saturated
Thermal lifting is also called __________ and is caused when cool air is over a warm surface and is heightened by intense solar heating.
convective lifting
Names of middle clouds contain the prefix
alto-
If the CB cloud extends past the __________, it is considered a severe thunderstorm.
Tropopause
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 Moisture
How do the winds shift during a cold front passage?
SW to NW
Squall lines generally develop where?
50 – 300 miles ahead of the cold front
What parameters of an air mass are generally uniform when measured across a horizontal plane?
Temperature and moisture
A line of violent thunderstorms that forms ahead of a cold front is known as a
squall line.
Every front is located in a
low pressure trough.
Which frontal system has a steeper slope?
A cold front.
How do the winds shift during a cold front passage?
SW to NW (SG says SW to NW, Answer Key says S to N)
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 an occluded front is generally located __________ NM south to
__________ NM north of the frontal intersection.
50;250
A line of rapidly forming thunderstorms is normally associated with
a dry line.
What type of weather is usually associated with a stationary front?
Weather similar to a warm front, but usually less intense
Occluded fronts form when a faster moving cold front overtakes a slower moving __________ front.
warm
A dry line, also called a dew point line, is a boundary between __________ air masses and can rapidly trigger
severe thunderstorms.
moist and dry
The four levels of intensity of turbulence are __________, __________, __________, and __________.
light, moderate, severe; extreme.
The four classifications of turbulence are __________, __________, _________, and _________.
thermal, mechanical, frontal; wind shear
What type of frontal activity is likely to produce the most turbulence?
fast moving cold front
All of the following are methods to combat turbulence except
rigorously hold your altitude.
What are the four levels of turbulence intensity?
Light, moderate, severe, extreme
Possible actions to mitigate mountain wave turbulence include all of the following except
maximize airspeed to minimize exposure time.
Turbulence occurring less than 1⁄3 of the time is described as
occasional.
Wind shear can be defined as
the change in wind direction and/or wind speed over a specific horizontal or vertical distance
Mountain wave turbulence updrafts and downdrafts can displace an aircraft up to __________ feet per minute.
5000
Mountain wave turbulence updrafts and downdrafts can displace an aircraft up to __________ feet per minute.
5000
What two units are used to measure atmospheric pressure?
Inches of Mercury (inHg) and millibars (mb)
What is standard Day temperature lapse rate?
2C (3.5F) per 1000 feet
Winds in the jet stream average between __________ and __________ knots, but can be as high as
__________.
100; 150;250
Describe intermittent precipitation.
Stops and starts at least once during the hour, may be showery or steady, associated with cumuliform or stratiform
How are occluded fronts indicated on a weather chart?
Alternating cold front and warm front symbols pointing in opposite directions
Where do squall lines usually develop?
50 to 300 miles ahead of a cold front, roughly parallel
A sudden change in wind speed or direction over short distance, vertically or horizontally describes what?
Wind Shear
What are the four turbulence classifications?
Light, moderate, severe, extreme
What type of icing is found in cumuliform clouds and unstable conditions?
Clear
There is a definite possibility of moderate icing, usually mixed or clear, within __________ to __________
miles ahead of the warm-front surface position.
100;200
Occasionally refer to the __________ for the most up to date icing severity definitions and how to report them
appropriately.
Flight Information Handbook (FIH) Airmen’s Information Manual (AIM)
The most profound degradation of structural icing that manifests on aircraft performance usually occurs within
__________ of ice accretion.
The first few minutes
What are the greatest hazards associated with engine icing?
Reduced airflow and engine FOD
What are the two types of icing?
Structural and engine
Air intake icing requires __________ moisture and __________ temperatures.
visible; sub-freezing
When icing conditions are encountered, pilots should __________ or __________ the icing condition.
Climb Above, Descend Below
After takeoff from a runway covered by snow or slush, operate the __________ several times to expel wet
snow or slush and to prevent freezing.
Brakes; gear and flap
What type of icing is found in cumuliform clouds and unstable conditions?
Clear
Slant-range visibility is the visibility from the __________ and features ahead.
cockpit to the ground
A ceiling is the height ascribed to the lowest layer of clouds or obscuring phenomena when it is reported at
least __________ and not classified “thin” or “partial” as determined by the summation principle.
2/8
Fog occurs when __________ are brought close together.
temperature and dew point
If an aircraft encounters an ash cloud in flight what is the best procedure for the pilot to use to escape the
cloud?
Execute a 180° turn
__________ visibility is the greatest horizontal visibility equaled or exceeded throughout at least half the
horizon circle which need not necessarily be continuous.
Prevailing
Total visibility over half the horizon circle or greater is
Prevailing Visibility
The lowest layer of clouds or obscuring phenomena when it is reported as broken, overcast, or obscuration and
not classified “thin” or “partial” as determined by using the summation principle” best describes
a ceiling
In order for fog to form, the three basic conditions of __________, __________, and __________ are
required.
condensation nuclei, low temperature/dew point spread; light surface winds
The key to dealing with volcanic ash is
avoidance
Roll and wall clouds indicate
low level wind shear and extreme turbulence.
Lightning strikes on aircraft commonly occur within __________ feet of the freezing level.
5,000
Be at least __________ feet higher than the top of the storm for every 10 knots of wind speed at the cloud top.
1000
If you find yourself with no other alternatives but to penetrate an area of thunderstorms, penetrate __________
to minimize time in the storm.
perpendicular
What combination of atmospheric conditions is necessary for the formation of a thunderstorm?
Moisture, unstable air, lifting action
What effects can turbulence have on an aircraft?
Altitude deviations, structural damage, airframe stress
What hazards are associated with lightning?
Structural damage, flash blindness, static buildup
Roll and wall clouds indicate
a severe and fast-moving thunderstorm.
A __________ forms on the surface at the leading edge of an advancing thunderstorm.
gust front
Microbursts are an intense, highly localized downward atmospheric flow with velocities of up to __________
feet per minute.
6000
Which of the following is not a valid method of identifying a microburst?
The presence of structural icing
If landing during microburst conditions, do not __________ power to idle until safely on the ground.
decrease
Wind speeds as high as __________ mph are possible in extreme microburst cases.
150
Microburst development is generally seen during the __________ months of the year.
Warmer
A microburst is a __________, formed in a thunderstorm, less than __________ miles in diameter.
downdraft (sinking air); 2.5
A METAR is a normally scheduled __________ airfield observation taken between __________ and
__________ minutes past the hour.
hourly; 55; 59
The two types of routine weather observation reports are the
METAR and SPECI.
A(n) __________ is an unscheduled observation containing all the data elements found in a METAR
whenever critical data have changed from the previous observation.
SPECI
The two sections that make up a METAR are the __________ section and the __________ section.
Body;Remark
Definitions for the particular weather phenomena abbreviations can be found in Chapter 10 of __________.
AFMAN 15-111
What is the minimum sky coverage constituting a ceiling?
5/8 to 7/8
From the TAF shown in Figure 13-31, what is the worst forecast ceiling for KDLF for 2000Z?
800 Feet
Using the TAF shown in Figure 13-32, what are the forecast winds for KEND at 030800Z?
200° at 10 knots
Using the TAF shown in Figure 13-33, what is the altimeter setting for KCBM at 1500Z?
20.08
What is a Terminal Aerodrome Forecast (TAF)?
An airport forecast for a specific period used to determine VFR or IFR flight plan requirements
Using the TAF shown Figure 13-34, what would be the lowest visibility forecast, in meters, with an ETA of
2030Z at KGRK?
6000
Using the TAF shown Figure 13-35, when is the lowest ceiling forecast for KRND?
0700Z–1500Z on the 7th
TEMPO forecasts do not supersede previous forecasts for their valid time.
TEMPO
