W02 Clouds and Meteors Flashcards
1
Q
Define Cloud
A
A Hydrometeor consisting of minute particles of liquid water or ice, or of both suspended, in the free air and usually not touching the ground.
2
Q
Define Layer Cloud, andWhat cloud form is a layer cloud?
A
A cloud which generally has significant horizontal extent but not great vertical extent.Stratiform
3
Q
What type of precipitation (continuous, showery, or intermittent) could come from layer clouds?
A
Could be either continuous or intermittent
4
Q
How much turbulence and/or icing would usually be associated with a layer cloud?
A
Ranges from None to Moderate
5
Q
Define Vertical Development Cloud, andWhat cloud form is a vertical development cloud?
A
A cloud which has moderate or great vertical extent.Cumuliform
6
Q
How much turbulence and/or icing would be usually be associated with a vertical development cloud?
A
Moderate to Severe
7
Q
What type of precipitation (continuous, showery, or intermittent) could come from cumuliform clouds?
A
Showery
8
Q
What are the 3 basic cloud forms?
A
StratiformCumuliformCirriform
9
Q
Define Stratiform Cloud
A
Clouds composed of rolls or elements, sometimes uniform in structure and normally stretched out in layers.
10
Q
Define Cumuliform Cloud
A
Clouds which are composed of individual elements or bases and tend to have large vertical extent.
11
Q
Define Cirriform Cloud
A
Clouds which are found in the upper portions of the sky and are ALWAYS composed of ice crystals
12
Q
Clouds other than cirriform clouds may be composed of ____________________________
A
ice crystals, water droplets, or a combination of both.
13
Q
What is the height range for the low etage?
A
near sfc to 6500 ft
14
Q
What is the height range for the middle (Alto) etage?
A
6600 to 19000 ft
15
Q
What is the height range for the high etage?
A
20000 feet & abv
16
Q
List the 14 cloud types reported in Canadian hourly wx reports. Name AND abbreviation.
A
Stratus Fractus - SFStratus - STNimbostratus - NSStratocumulus - SCCumulus Fractus - CFCumulus - CUTowering Cumulus - TCUCumulonimbus - CBAltostratus - ASAltocumulus - ACAltocumulus Castellanus - ACCCirrus - CICirrostratus - CSCirrocumulus - CC
17
Q
Which of the 14 cloud types belong to the LOW etage? (Answer written in abbreviations)
A
SF, ST, NS, SC, CF, CU, TCU, CB
18
Q
Which of the 14 cloud types belong to the MIDDLE etage? (Answer written in abbreviations
A
AS, AC, ACC
19
Q
Which of the 14 cloud types belong to the HIGH etage? (Answer written in abbreviations
A
CI, CS, CC
20
Q
Define “Nimbus” / “Nimbo”
A
Giving or capable of giving precipitation
21
Q
Define “Alto”
A
In the middle levels
22
Q
Define “Fractus”
A
Broken up, Fragments
23
Q
Define “Towering” or “Congestus”
A
Vertical Development
24
Q
Define “Castellanus”
A
Turrets or Towers
25
Define "Floccus"
small cumuliform tufts, lower part ragged
26
Define "Lenticular"
Almond/lens/cigar shaped
27
Define "Mamma"
Pouchy, breast-like hangings on the underside of a cloud
28
Define "Virga"
Precipitation not reaching the ground
29
Describe Stratus Fractus
Grey colour cloud with diffuse irregular shreds.Near sfc to 1500 ft - usually very low100 to 1000 feet thickComposed of Water droplets, ice crystals, and super-cooled water dropletsNo precipitation
30
Describe Stratus
Light to medium grey colour uniform layer. Resembles fog, but not resting on sfc. Gives the sky a hazy appearance. Often has a ragged base. Near sfc to 1500 ft - usually in lower levels100 to 3000 feet thickComposed of Water droplets, ice crystals, and super-cooled water dropletsDrizzle, Freezing Drizzle, Snow Grains, Snow
31
Describe Nimbostratus
Very dense in a low diffuse rainy layer. Medium to dark grey in colour. Usually nearly uniform (little elementing), may be ragged. Feebly illuminated, seemingly from inside. Diffuse wet-looking base. Generally have SF or ST forming below in precipitation.Near sfc to 6500 Ft, usually below 5000 ft.4000 to 20000 feetComposed of Water droplets, ice crystals, and super-cooled water droplets - usually top portions are ice crystals.Rain, Snow, Ice Pellets, Freezing Rain
32
Describe Stratocumulus
Layer of patches of globular masses or rolls, with fairly large elements. Soft and grey with darker parts. Elements arranged in groups, lines, or waves, aligned in one or two directions.Near sfc to 6500 feetUp to 3000 feet thickWater droplets and/or ice crystals, supercooled water droplets, mixture of water droplets and ice crystals RARE in SC. Usually no precipitation. If any, light snow, light rain, light snow pellets if vertical development cloud embedded.
33
Describe Cumulus Fractus
White to light grey colour with dense centres. Ragged edges show constant change. Rounded shape, lacking the flat bases of CU. Appears white in the sun, and dark in bad weather.Near sfc up to 2000 feet. Bad weather = usually very lowSmall vertical extent, usually no more than 500ftwater droplets.Nil precipitation.Often forms below NS in precipitation.
34
Stratus Fractus abbreviation
SF
35
Stratus abbreviation
ST
36
Nimbostratus abbreviation
NS
37
Stratocumulus abbreviation
SC
38
Cumulus Fractus abbreviation
CF
39
Cumulus abbreviation
CU
40
Towering Cumulus abbreviation
TCU
41
Cumulonimbus abbreviation
CB
42
Altostratus abbreviation
AS
43
Altocumulus abbreviation
AC
44
Altocumulus Castellanus abbreviation
ACC
45
Cirrus abbreviation
CI
46
Cirrostratus abbreviation
CS
47
Cirrocumulus abbreviation
CC
48
Describe Cumulus
Dense clouds appearing white in the sun, but dark central portions overhead. Flat bases and rounded tops. Individual bases.1000 to 6500 feet. Note that bases can be much higher in the summer and can become progressively higher as the afternoon goes on.500 to 5000 feet thickWater droplets, occasionally supercooledForms in the morning and dissipates in the evening-SHSN or -SHRA
49
Describe Towering Cumulus
Dense clouds that appear white in the sun but dark overhead with flat bases. Considerable vertical development with a hard "cauliflower" outline1500 to 6500 feet bases that can be much higher in summer.5000 to 20000 feet thickWater droplets, supercooled water droplets, ice crystalsSHRA, SHSN, SHPL, SN (snow pellets)Distinguished from cumulus by heavy active tops or towers, and from cumulonimbus by absence of ice crystal structure of top.
50
Give the physical description of SF
Grey colour, diffuse irregular shreds
51
How high is SF usually found?
It is usually very low, near the surface up to 1500 feet.
52
How thick is SF?
100-1000 feet thick?
53
What is SF composed of?
Water dropletsIce crystalsSuper-cooled water droplets
54
How is SF formed?
-The breaking up of stratus-formed in precipitation below AS or NS-the lifting and breaking up of fog-orographic lifting
55
What kind of precipitation is produced by SF?
None
56
Describe Cumulonimbus
Dark grey (almost black) from below. Very dense water portions. Cirriform head fairly diffuse, but more dense than most cirriform cloud. Turbulent with strong vertical currents resulting in great vertical developments. Upper parts are fibrous frequently in the form of an anvil. Base often very ragged and can be confused with NS. 1500 to 6500 feet10000 to 40000 feet thick or greater3 distinct regions - water droplets in lower portions, supercooled water droplets and ice crystals in middle levels (above freezing level), and ice crystals in the upper levels.SHRA, SHSN, GR (hail), Snow Pellets, Ice Pellet Showers, Can produce VIOLENT showersLTNG (LTGCG, LTGCC, LTGIC) , Thunder, SVR TURB, LLWS, Microburst
57
Describe
TBA
58
What are the characteristics of ST?
A uniform layer that is light to medium grey. It resembles fog but doesn't rest on the surface. It gives the sky a hazy appearance and often has a ragged base.
59
What height is ST usually at?
Near the surface to 1500ft
60
How thick can ST be?
100-3000 feet thick
61
What is ST composed of?
Water dropletsSuper cooled water dropletsIce crystals
62
How does ST form?
-May form from SC-May be formed by a for layer lifting-orographic lifting-In precipitation-by merging of SF
63
What kind of precipitation does ST produce?
Drizzle or freezing drizzleSnow grainsSnow
64
What are the characteristics of NS?
It is a very dens, low, diffuse layer that is medium to dark grey. It is a uniform layer with a diffuse, wet looking base that looks illuminated from the inside. Often, there are low SF or ST forming below.
65
How high can NS be found?
Near surface to 6500 feet
66
How thick is NS?
4000-20,000 feet thick
67
What is NS composed of?
Water dropletsSuper cooled water dropletsIce crystals(usually in the top portions)
68
How is NS formed?
When AS thickens and lowersEvolving from SC and ACFrontal lifting, convergence or orographic lift
69
What kinds of precipitation are formed by NS?
RainSnowIce pelletsFreezing rain
70
What are the characteristics of SC?
Layer or patches of globular masses or rolls that are fairly large. Soft and grey with some darker parts. Elements are arranged in groups, lines, or waves aligned in one or two directions
71
What height are SC found at?
Near surface to 6500 feet
72
How thick is SC?
Up to 3000 feet
73
What is SC composed of?
Water dropletsWater droplets and ice crystalsSuper cooled water droplets
74
How is SC formed?
Spreading out of CU CB or TCUMay form from STMay form from orographic list or mechanical turbulence
75
What kinds of precipitation is produced by SC?
Usually noneSometimes light rain, light snow, light snow pellets
76
What are the characteristics of CF?
They are white to light grey colour with a dense centre and ragged edges showing constant change. It has a roundish shape, but no flat bottom and looks white in the sun but dark when of bad weather.
77
What is the height of CF?
Near the surface to 2000 feet
78
How thick is CF?
Up to 500 feet thick
79
What is CF composed of?
Water droplets
80
How is CF formed?
By the breaking up of other clouds by windCan be formed by thermal lifting orographic lifting
81
What kind of precipitation does CF produce?
None
82
What are the characteristics of CU?
Individual elements that are dense with a white, rounded top, and a dark, flat base.
83
At what height is CU found?
1000-6500 feet. Higher in the summer and higher as an afternoon goes on.
84
How thick is CU?
500-5000 ft
85
What are CU composed of?
Water dropletsSuper cooled water droplets
86
How are CU formed?
Daytime heatingOrographic liftingFrom CF
87
What precipitation does CU produce?
Light showers of rain or snow.
88
What are the characteristics of TCU?
A dense cloud with a flat base that appears white in the sun but dark overhead with considerable vertical development and a hard cauliflower outline.
89
At what height can TCU be found?
1500-1600 feet high
90
How thick are TCU?
5000-20,000 feet thick
91
What are TCU composed of?
Water dropletsSuper cooled water dropletsIce crystals
92
How is TCU formed?
Thermal, orographic, or frontal liftingFrom further developing of CU
93
What kind of precipitation does TCU produce?
Rain showersSnow showersIce pellet showersSnow pellets
94
What are the characteristics of CB?
A very dark grey base with great vertical development. Very dense water portions and a ragged base. Upper parts of the cloud are fibrous and can form an anvil shape
95
How high are CB found?
1500-6500 feet
96
How thicker are CB?
10,000-40,000 feet thick
97
What are CB composed of?
Water dropletsSuper cooled water dropletsIce crystals
98
How is CB formed?
Thermal, orographic,or frontal liftingDevelopment of TCU
99
What kind of precipitation does CB produce?
Rain showersSnow showersHailSnow pelletsIce pellet showers
100
What are the characteristics of AS?
One uniform layer of a grey or bluish colour that makes the sun or moon look as though viewed through ground glass and does not produce a shadow.
101
How high can AS be found?
6600-19,000 feet
102
How thick are AS?
1000-10,000 feet thick
103
What is AS composed of?
Water dropletsWater droplets and/or ice crystalsSuper cooled water droplets
104
How is AS formed?
From ACFrontal liftingLifting due to convergence
105
What types of precipitation does AS produce?
Rain or freezing rainSnowIce pellets
106
What are the characteristics of AC?
White or grey flattened globular masses with fairly small regularly arranged elements. Elements are arranged in lines, groups, or waves following one or two directions
107
How high are AC found?
6600-19,000 feet
108
How thick are AC?
100-3000 feet thick
109
What are AC composed of?
Water dropletsWater droplets and/or ice crystalsSuper cooled water droplets
110
How are AC formed?
From ASSpreading out of TCU or CBFrontal lifting or lifting due to convergence
111
What kind of precipitation do AC produce?
Usually none, but sometimes intermittent rain or snow
112
What are the characteristics of ACC?
White to light grey with a common flat base. Have slight vertical development, resembling turrets of a castle.
113
How high are ACC found?
6600-19,000 feet high
114
How thick are ACC?
500-2000 feet thick
115
What are ACC composed of?
Water droplets or ice crystals
116
How are ACC formed?
Updrafts that are small in diameter
117
What kind of precipitation do ACC produce?
Possible showers or dry microbursts. Virga very common.
118
What are the characteristics of CI?
Pure white, fibrous filaments with a silky appearance. Look like they have tufts, hooks, and commas.
119
How high are CI found?
20,000-40,000 feet
120
How thick are CI?
300-1000 feet thick
121
What are CI composed of?
Ice crystals
122
How are CI formed?
By frontal overrunning or convergenceFrom tops of CB
123
What kinds of precipitation are produced by CI?
None
124
What are the characteristics of CS?
Pure white, continuous fibrous layer through which the outline of the sun or moon is clearly visible. Halo is common
125
How high are CS found?
20,000-40,000 feet
126
How thick is CS?
300-1000 feet
127
What are CS composed of?
Mostly ice crystals
128
How are CS formed?
Frontal overrunning or convergence
129
What types of precipitation do CS produce?
None
130
What are the characteristics of CC?
Pure white small globular masses arranged in groups or lines. Ripples described as sand on the seashore.
131
How high are CC found?
20,000-40,000 feet
132
How thick are CC?
100-700 feet thick
133
What are CC composed of?
Ice crystalsVery rarely super cooled water droplets
134
How are CC formed?
Turbulent overrunning airBreaking up of CS
135
What types of precipitation do CC produce?
None.
136
What type of clouds give continuous or intermittent precipitation?
Layer clouds
137
What type of clouds give showery precipitation?
Vertical development clouds
138
What is the only cloud that can produce DZ or FZDZ, and Snow Grains?
Stratus
139
Define Meteor
A phenomenon observed in the atmosphere or on the surface of the earth. It consists of a suspension, precipitation, or a deposit of aqueous or non-aqueous liquid or solid particles, or a phenomenon of the nature of an optical or electrical manifestation.
140
Define Hydrometeor
A meteor consisting of an ensemble of liquid or solid water particles suspended in or falling through the atmosphere, blown by the wind from the earth's surface, or deposited on objects on the ground or in the free air.
141
Fog is an example of what type of meteor?
Hydrometeor
142
Blowing Snow is an example of what type of meteor?
Hydrometeor
143
Define Lithometeor
A meteor consisting of an ensemble of particles, most of which are solid and non-aqueous. The particles are more or less suspended in the air or lifted from the ground by the wind.
144
Smoke is an example of what type of meteor?
Lithometeor
145
Define Photometeor
A luminous phenomenon produced by the reflection, refraction, diffraction, or interference of light from the sun or moon.
146
A Halo phenomena is an example of what type of meteor?
Photometeor
147
Define Electrometeor
A visible or audible manifestation of the atmospheric electricity
148
Name a Hydrometeor in Suspension (3 options)
Fog (FG)Freezing Fog (FZFG)Mist (BR)
149
What is the difference between Fog and Mist? (FG vs BR)
Fog reduces visibility to 1/2 SM or less at the surface, whereas Mist reduces visibility to 5/8 to 6SM (inclusive)
150
How can we tell the difference between Drizzle and Rain?
Drizzle drops are less than 0.5mm diameter, and are too small to make ripples on standing water (puddle, lake, etc.)
151
Name a Hydrometeor as precipitation (4 options)
Drizzle, Rain, Freezing Drizzle, Freezing Rain
152
Name a Hydrometeor as frozen precipitation (7 options)
Snow (SN)Snow Pellets (SHGS)Snow Grains (SG)Ice Pellets (PL)Hail (SHGR)Small Hail (SHGS)Ice Crystals (IC)
153
Name a Hydrometeor as particles raised by the wind (3 options)
Blowing Snow (BLSN)Drifting Snow (DRSN)Spray
154
Name a Lithometeor in suspension (4 options)
Haze (HZ)Dust Haze (DU)Smoke (FU)Volcanic Ash (VA)
155
Name a Lithometeor raised by the wind (7 options)
Dust/Sand Whirls (PO)Blowing Dust (BLDU)Blowing Sand (BLSA)Duststorm (DS)Sandstorm (SS)Drifting Dust (DRDU)Drifting Sand (DRSA)
156
Name a Photometeor (5 options)
Halo phenomenaCorona (usually indicates AC)IrisationGloryRainbow
157
Define the Photometeor "Glory"
One or more sequences of coloured rings seen by an observer around his own shadow on a cloud consisting mainly of numerous small water droplets, on fog, or rarely, dew.
158
Name an Electrometeor (5 options)
ThunderstormLightingThunderSaint Elmo's FireAurora
