Block 4 Flashcards
(205 cards)
1
Q
When are convective currents most active?
A
Warm summer afternoons
2
Q
Which cloud form often produces widespread IFR weather?
A
Stratiform
3
Q
WS identifies what?
A
SIGMET
4
Q
How would you say 22015G25 180V250 ?
A
“Wind 220 at 15 gusts 25. Wind variable between 180 and 250.”
5
Q
What is the raw material for clouds and precipitation?
A
Water vapor
6
Q
What are the 3 types of structural icing?
A
Rime
Clear
Mixed
7
Q
A layer in which temperature increases with altitude
A
Temperature inversion
8
Q
What is issued when specified conditions are expected to affect at least 3,000 square miles?
A
SIGMET
9
Q
Which 3 ingredients are required for the formation of precipitation?
A
Water Vapor
Lift
Growth Process
10
Q
A boundary or transition zone between two air masses of different density and (usually) of different temperature is called _______.
A
A front
11
Q
A sinking parcel of air compresses and _____ as it encounters increasing pressure; this causes a cloud to quickly ______.
A
Warms ; dissipate
12
Q
What clouds resemble white fluffy cotton balls?
A
Cumuliform
13
Q
What cloud may produce icing, turbulence and other hazards?
A
Cumuliform
14
Q
Which gas constitutes only a small percentage of the earth’s atmosphere and varies widely in both time and space, ranging from trace amounts to 4% by volume?
A
Water vapor
15
Q
A Maritime Tropical air mass is ______ and ______.
A
Warm and moist
16
Q
The weather phenomena VA stands for:
A
Volcanic Ash
17
Q
Water particles that reach the ground
A
Precipitation
18
Q
What is a continental moisture?
A
Dry air mass that develops over land.
19
Q
Air flow around a low:
Converges or Diverges
A
converges
20
Q
Turbulent vertical motions that result from subsequent rising and sinking of air.
A
Convective Turbulence
21
Q
The weather phenomena +FC stands for:
A
Funnel Cloud touching the ground (tornado or waterspout)
22
Q
Which product would provide a forecast of IFR over Georgia and Atlanta?
A
AIRMET SIERRA
23
Q
Which product would provide a forecast of sustained surface wind greater than 30 kts over Minnesota and Iowa?
A
AIRMET TANGO
24
Q
A front that moves in such a way that warmer air replaces colder air.
A
Warm Front
25
The maximum valid period for a SIGMET is ____.
4 hours (or 6 hours outside continental US)
26
This type of turbulence causes abrupt changes in attitude or altitude. May be momentarily out of control.
Severe (SEV)
27
What is a maritime moisture?
Moist air mass which develops over water.
28
In regards to turbulence, what is "chop" and in what forms can it be reported?
Light or Moderate Chop
Bumpiness without appreciable changes in altitude or attitude
29
This type of icing may require occasional use of deicing equipment and will not present a problem if the deicing equipment is used.
Light (LGT)
30
How long are AIRMETs valid for?
No more than 6 hours
31
AIRMET SIERRAs are for:
IFR and mountain obscuration
32
Which type of front creates towering clouds?
Cold fronts
33
What are the elements listed on the PIREP form called?
Text Element Indicators (TEIs)
34
SIGMETs are issued for which weather phenomenas?
Any severe weather, widespread dust storms (DS), sandstorms (SS) or volcanic ash (VA).
35
The weather phenomena UP stands for:
Unknown Precipitation
36
Which front moves in such a way that warmer air replaces colder air?
Warm front
37
Rising air ______ and ______.
expands and cools
38
A downburst that covers an area greater than 2.5 miles alongside peak winds as high as 120 kts and can last from 5-30 minutes is called _______.
Macroburst
39
Which 3 systems alerts ATC of microbursts, wind shear and gust fronts?
LLWAS
TDWR (terminal doppler wx radar)
ASR/WSP (Weather system processor)
40
The weather phenomena GS stands for:
Small hail and/or snow pellets
41
What clouds indicate uplift of air?
Cumuliform
42
How would you say FEW000 if there are remarks explaining the obscurations?
"Sky partially obscured"
43
Highs have warm air which can hold more water vapor thus clouds tend to ________.
Evaporate
44
When is RVR reported?
When visibility is 1SM or less and/or
| 6000ft or less
45
How would you say R25L/M0800FT ?
"Runway 25L RVR less than 800."
46
An RVR proceeded by a "P" (ex R16/P6000FT) means ______.
RVR is "More than" the number reported
47
Which produce would provide a forecast of severe icing over Kentucky?
SIGMET
48
How would you say: "KOKC 032203Z AUTO"
"Oklahoma City Airport Automated two two zero three Observation..."
49
Which precipitation type occurs when there is a shallow layer aloft with above freezing temperatures, with a deep layer of below freezing air at the surface?
Ice Pellets (PL)
50
How would you say R17L/2400V3000FT ?
"Runway 17L RVR variable 2400 to 3000."
51
Convective SIGMETs are issued when severe thunderstorms have:
Winds >50kts
Hail 3/4" or greater
Tornatoes
52
What are the 4 classifications of turbulence?
Light (LGT)
Moderate (MOD)
Severe (SEV)
Extreme (EXTRM)
53
What will happen when the temperature-dew point spread decreases to zero?
The air becomes saturated and condensation will form dew or fog
54
This type of turbulence will cause the aircraft to move somewhat, but the aircraft will remain in positive control at all times.
Moderate (MOD)
55
What cloud is like a layer or blanket?
Stratiform
56
Are Convective SIGMETs scheduled or unscheduled?
Scheduled
57
Good visibility and turbulence are associated with ____ fronts.
Cold
58
Which layer of the atmosphere is stable and generally devoid of significant weather?
Stratosphere
59
Which of the following clouds would be visual proof of a mountain wave?
Rotor cloud
60
VV005 would be said as "________."
"Indefinite Ceiling 500."
61
What type of front has a steep slope which often leads to a narrow band of showers and thunderstorms if the rising air is unstable?
Cold front
62
In a TAF, what indicates a significant and rapid change?
FM
63
Within which layer of the atmosphere does temperature increase with altitude, making it a stable layer, generally devoid of significant weather?
Stratosphere
64
How would you say SCT000 if there are remarks explaining the obscurations?
"Sky partially obscured"
65
Snow lifted to a height of 6 ft or more above the ground reducing visibility to less than 7 SM
Blowing Snow
66
Ice that sticks to the outside of an airplane is called:
Structural icing
67
How would you say BKN000 if there are no remarks?
"Ceiling less than five zero broken"
68
A large body of air that has similar horizontal temperature and moisture characteristics defines _______.
Air Mass
69
The weather phenomena SG stands for:
Snow grains
70
What are the two commonly identified jet streams?
Polar Jet Stream
| Subtropical Jet Stream
71
Although _______ is the most common type of icing, it is the least serious because it is easiest to remove.
Rime
72
The ratio of water vapor in the air compared to the amount of water vapor the air can hold at a particular temperature and pressure is the definition of _______.
Relative humidity
73
What level of turbulence do mountain waves produce?
Severe-Extreme
74
Rough, milky, opaque ice formed by the instantaneous freezing of small super-coolded water drops after they strike the aircraft
Rime ice
75
What is the standard temperature?
15 deg C, 59 deg F
76
In order to escape icing, a pilot must do what 3 things?
1. Exit the area of visual moisture
2. Climb or descend to positive temperatures
3. Climb to altitudes where temperatures are too cold to support supercooled droplets
77
This type of turbulence causes slight, erratic changes in pitch/roll/yaw
Light (LGT)
78
What type of air mass produces stable air that is associated with smooth air, poor visibility and stratiform clouds?
Warm air over cold surface
79
Thunderstorm tops can commonly extend into the lower ________.
Stratosphere
80
The qualifier MI stands for:
Shallow
81
AIRMET ZULUs are for:
Icing/FreeZing
82
Wind direction is considered to be variable when during the 2-minute evaluation period, it fluctuates by 60 degrees or more.
Variable wind
83
The change of ice to water vapor is called ______.
Sublimation
84
Precipitation of transparent or translucent pellets of ice, which are round or irregular. Sometimes called "sleet"
defines _______.
Ice pellets (PL)
85
Turbulence is caused by these 3 things:
Convective currents
Obstructions to wind flow
Wind shear
86
What is the lowest and highest visibility that can be reported by an automated station?
M1/4SM and 10SM
87
An atmospheric wave disturbance formed when stable air flow passes over a mountain or mountain ridge
Mountain wave
88
What are the 3 temperature properties?
Arctic
Tropical
Polar
89
A _______ air mass moving over a _______ surface often produces unstable air associated with turbulence, good visibility, cumuliform clouds and showers.
cold ; warm
90
How would you say SCT000 if there are no remarks?
"Less than five zero scattered."
91
The weather phenomena PY stands for:
Spray
92
_____ reduces horizontal visibility to less than 5/8 SM, but does not fall to the ground
Fog
93
The weather phenomena PL stands for:
Ice Pellets
94
A glossy, clear or translucent ice formed by the relatively slow freezing of large super-cooled water drops.
Clear ice
95
A strong downdraft which induces an outburst of damaging winds on or near the ground is a ______.
Downburst
96
The qualifier BC stands for:
Patches
97
This type of turbulence is violent and may be impossible to control/cause structural damage.
Extreme (EXTRM)
98
What is mixed ice?
A mixture of clear and rime ice
99
Air flow around a low converges in which direction, and has what type of motion?
Counter-clockwise; rises
100
This type of icing could be hazardous even after a short encounter and will require deicing or even a flight diversion.
Moderate (MOD)
101
Which layer of the atmosphere contains almost all of the clouds and precipitation?
Troposphere
102
How would you say FEW000 if there are no remarks?
"Few clouds at less than five zero"
103
A high pressure system spins in which direction?
Highs spin clockwise
104
How would you say BKN000 if there are remarks explaining the obscurations?
"Sky partially obscured"
105
How long are Center Weather Advisories valid for?
2 hours
106
9900 in an FB indicates the wind is:
Light and variable
107
What are the 3 stages of a thunderstorm cell?
1. Towering cumulus
2. Mature (peak intensity)
3. Dissipating
108
WST identifies what?
Convective SIGMET
109
When temperature is missing, read /11 as ______.
"Temperature missing, dewpoint one-one."
110
What is the lowest layer of the atmosphere?
Troposphere
111
How would you say: "KOKC 011955Z COR...."
"Oklahoma City Airport Corrected one niner five five observation..."
112
Where will you find convective SIGMETs being issued?
Continental US
113
A parcel of ______ air expands and cools as pressure decreases with height.
rising
114
Which product would provide a forecast of freezing levels over New England?
AIRMET ZULU
115
Any of the forms of water particles that reach the ground is _________.
Precipitation
116
Turbulence caused by obstructions, such as trees, buildings, mountains, etc... is called ________.
Mechanical Turbulence
117
What cloud consists of a featureless low layer that can cover sky?
Stratiform
118
Which weather office provides consultation to ARTCCs?
Center Weather Service Units (CWSUs)
119
______ is an unscheduled weather advisory issued by CWSU meteorologists for ATC to use to alert pilots of existing or anticipated advises weather within the next 2 hours?
Center Weather Advisory (CWA)
120
Air flow around a low ______ in a counter-clockwise motion and _______ causing the air to cool and eventually condense into clouds and precipitation.
converges, rises
121
Which front is associated with poor visibility, smooth air and steady precipitation?
Warm front
122
Precipitation formation requires water vapor, lift and ______.
Growth
123
What 3 phases make up a downburst cycle?
Formation
Impact
Dissipation
124
Which air mass diverges in a clockwise motion and sinks?
A high
125
A storm produced by cumulonimbus (CB) clouds and always accompanied by lightning and thunder is a ________.
Thunderstorm
126
A composite of two fronts as a cold front overtakes a warm front or stationary front.
Occluded Front
127
Jet streams often produce what type of turbulence?
Clean Air Turbulence (CAT)
128
The interface or transition zone between two air masses of different density
Frontal Zone
129
_________ is an unscheduled discussion product issued by CWSU meteorologists that summarizes anticipated weather conditions with potential impact on air traffic flow control and flight operations in an ARTCC's area?
Meteorological Impact Statement (MIS)
130
A downburst that covers an area of up to 2.5 miles alongside peak winds up to 150 kts and can last from 2-5 minutes is called _______.
A Microburst
131
VV stands for ______ _______ and indicates what?
VV = Vertical Visibility
| Indicates an Indefinite Ceiling
132
What are the 4 classifications of icing?
Trace (TRACE)
Light (LGT)
Moderate (MOD)
Severe (SEV)
133
Rain that freezes on contact with the ground is _______.
Freezing Rain (FZRA)
134
Warm air over a cold surface creates which 3 things?
Smooth air
Poor visibility
Stratiform clouds, fog and drizzle
135
This type of icing will not require deicing equipment unless this type of icing is encountered for an extended period of time.
Trace (TRACE)
136
The weather phenomena DU stands for:
Widespread dust
137
How long are convective SIGMETs valid for?
2 hours
138
How would you say: "33037G46KT 300V010"
"Wind 330 37 gusts 46. Wind variable between 300 and 010."
139
Which precipitation types most commonly produce instrument weather?
Rain
Drizzle
Snow
140
What are the 2 moisture properties
Continental
| Maritime
141
What are the 3 cloud forms?
Cirriform
Cumuliform
Stratiform
142
What cloud produces little or no turbulence, but can produce icing?
Stratiform
143
An RVR proceeded by an "M" (ex R16/M5000FT) means ______.
RVR is "Less than" the number reported
144
Which body of water is NOT a primary source of water vapor?
The Salt Lake is NOT a primary source
145
Thunderstorm cell formation requires ______, unstable air, and lift.
Water vapor
146
Air flow around a high:
| Converges or Diverges
diverges
147
Sinking air _______ and ________.
compresses and warms
148
______ occurs when the temperature remains below freeing throughout the entire depth of the atmosphere.
Snow (SN)
149
How would you say R22R/P6000FT ?
"Runway 22R RVR more than 6000."
150
Temperature increases with altitude in the _______.
Stratosphere
151
The weather phenomena GR stands for:
Hail
152
What is the greatest cause of fatal accidents?
Visual flight into IFR conditions
153
The weather phenomena FC stands for:
Funnel Cloud (or tornado/waterspout)
154
Which adverse effect of structural icing is LEAST significant to an aircraft?
Increased drag
or
Increased weight
Increased Weight
155
The weather phenomena PO stands for:
Well-developed dust/sand whirls
156
The weather phenomena SS stands for:
Sand Storm
157
A maximum of atmospheric pressure on a surface weather chart. Also known as an anti-cyclone.
A high
158
The weather phenomena -FC stands for:
Funnel cloud not touching the ground
159
The weather phenomena SA stands for:
Sand
160
TAFs are issued by who?
The NWS
161
The weather phenomena DS stands for:
Dust Storm
162
If no temperature or dewpoint is displayed, read it as ______.
"Temperature missing, dewpoint missing."
163
How would you say: "...35013G34KT"
"Wind 350 at 13 gusts 34"
164
A minimum of atmospheric pressure on a surface weather chart. Also known as a cyclone.
A low
165
What are the requirements to solicit PIREPs?
```
Ceilings at or below 5,000ft
Vis 5mi or less
Thunderstorms
Turbulence
Icing
Wind Shear
Volcanic Ash
Braking Action Advisories
```
166
When dewpoint is missing, read 15/ as ______.
"Temperature one-five, dewpoint missing."
167
The qualifier PR stands for:
Partial
168
Relatively strong winds in the upper troposphere are known as the ________.
Jet Stream
169
What cloud can have tops reaching over 60,000ft?
Cumuliform
170
What is used in a TAF to show a 30% chance?
PROB30
171
Which product would be used to firecast an isolated severe thunderstorm 25 miles W of Hill City, KS?
Convective SIGMET
172
What are the five layers of the earth?
```
Exosphere
Thermosphere
Mesosphere
Stratosphere
Troposphere
```
173
Are SIGMETs scheduled or unscheduled?
Unscheduled
174
The qualifier DR stands for:
Low Drifting
175
Controllers shall advise pilots of hazardous weather that may impact operations within _____ NM of their sector.
150 NM
176
The weather phenomena IC stands for:
Ice Crystals
177
Cold air mass moving over a warm surface often produces (unstable or stable) air.
Unstable air
Cold over Warm = unstable
178
A front which is stationary or nearly so.
Stationary Front
179
Liquid water at temperatures below the freezing point and causes instant feezing
Supercooled Water
180
This type of icing is so quick/intense that deicing equipment fails to reduce the hazard. Immediate flight diversion is necessary.
Severe (SEV)
181
Change in wind direction of 45 degrees or more in less than 15 minutes, and has sustained winds of 10 kts or more is a ________.
Wind shift
182
Greatest distance that can be seen throughout at least half of the horizon circle.
Prevailing Visibility
183
_______ occurs when there is a deep layer aloft with above freezing temperatures and a shallow layer of below freezing air at the surface.
Freezing Rain (FZRA)
Drops freeze on contact with ground or exposed objects
184
The 3 ingredients for a thunderstorm cell are:
Water vapor
unstable air
lift
185
A low pressure system spins in which direction?
Lows spin counter-clockwise.
Lows-Left over the top
186
When the _______ is greater than zero, the air is unsaturated.
Temperature-dew point spread
187
AIRMET TANGOs are for:
Moderate Turbulence
Winds >30 kts
LLWS
188
SIGMETs
Convective SIGMETs
AIRMETs
Which are scheduled and which are unscheduled?
SIGMET: Unscheduled
Convective SIGMET: Scheduled
AIRMET: Scheduled
189
When temperature-dew point spread ________, relative humidity _______.
Temperature-dew point spread DECREASES, Relative humidity INCREASES.
Temp-dew point |v|
Relative humidity |^|
190
If the wind in an FB is reported at FL300 as 760050, what is the wind and temperature?
260 at 100. Temperature -50
191
What are the two types of PIREPs?
Urgent (UUA)
| Routine (UA)
192
When the air is too dry for cumuliform clouds to form, _____ currents caused by uneven surface heating can still be active and cause turbulence.
Convective
193
A front that moves in such a way that colder air replaces warmer air.
Cold Front
194
The weather phenomena SQ stands for:
Squalls
195
Which type of air condenses thus forming clouds and precipitation?
Cooling air
196
What generates turbulence between two wind currents of differing wind directions and/or speeds?
Wind shear
197
Poor visibility, smooth air and steady precipitation are associated with _____ fronts.
Warm
198
Cold air over a warm surface creates which 3 things?
Turbulence
Good Visibility
Cumuliform clouds and showers
199
What is responsible for most weather-related accidents?
Wind
200
Pressure usually _______ as a front approaches and _______ after it passes.
decreases ; increases
201
What does DSNT stand for?
Weather beyond 10SM
202
How would you say: "SPECI KOKC 222108Z..."
"Oklahoma City Airport Special Report, zero eight observation."
203
A forecast of non-convective LLWS would be found in what NWS product?
TAF
204
Which precipitation type occurs when there is a deep layer aloft with above freezing temperatures, with a shallow layer of below freezing air at the surface?
Freezing rain (FZRA)
205
A warm air mass moving over a cold surface produces (unstable or stable) air.
Stable air
Warm over Cold = stable
