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Flashcards in Clouds Deck (55)
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1

Cirrostratus

Origin:  from Cirrus (Latin: curl, tuft, fringe) + Stratum (Latin: a covering)

Altitude: High (>7000 m)

Discription: Transparent, whitish veil clouds with a fibrous (hair-like) or smooth appearance. A sheet of cirrostratus which is very extensive, nearly always ends by covering the whole sky.

Compositon: Ice Crystals

Sunlight: Produces an halo around the sun or moon.

Weather Indications:  Usually come 12 to 24 hours before a rain or snowstorm

Possible Confusion: A milky veil of fog (or thin Stratus) is distinguished from a veil of Cirrostratus of a similar appearance by the halo phenomena which the sun or the moon nearly always produces in a layer of cirrostratus. The halo is the width of your hand held at arm's length.

 

2

Cirrus

Origin:  from Latin: curl, tuft, fringe

Altitude: High (>7000 m)

Discription: Detached clouds in the form of white, delicate filaments, mostly white patches or narrow bands. They may have a fibrous (hair-like) and/or silky sheen appearance.

Compositon: always composed of ice crystals, and their transparent character depends upon the degree of separation of the crystals.

Sunlight: As a rule when these clouds cross the sun's disk they hardly diminish its brightness. Before sunrise and after sunset, cirrus is often colored bright yellow or red. These clouds are lit up long before other clouds and fade out much later.

Weather Indications: Cirrus clouds are often seen during fair weather. But if they build up larger over time and are followed by cirrostratus clouds, there may be a warm front on the way. 

3

Altocumulus

Origin:  from Altus (Latin: high) + Cumulus (Latin: mass, pile)

Altitude: Middle (7000m>2000 m)

Discription: One part of cloud darker than another. White and/or gray patch, sheet or layered clouds, generally composed of laminae (plates), rounded masses or rolls. They may be partly fibrous or diffuse.  Altocumulus clouds usually form in groups and are about one kilometer thick. Altocumulus clouds are about as wide as your thumb when you hold up your hand at arm's length. 

Compositon: Chiefly consist of super-cooled water droplets of minus 10C, but ice crystals are often present. 

Sunlight: When the edge or a thin semitransparent patch of altocumulus passes in front of the sun or moon a corona appears. This colored ring has red on the outside and blue inside and occurs within a few degrees of the sun or moon.

Weather Indications:  If in the morning, often thunderstorms by late afternoon as it shows instability and convection in the middle levels of the troposphere, the area where towering cumulus clouds can turn into cumulonimbus.

Possibel Confusion: Similar to cirrocumulus, but individual segments are larger and darker.

4

Cumulus

Origin: Cumulus (Latin: mass, pile)

Altitude: Low (<2000 m)

Description: Detached, generally dense clouds and with sharp outlines that develop vertically in the form of rising mounds, domes or towers with bulging upper parts often resembling a cauliflower.; The sunlit parts of these clouds are mostly brilliant white while their bases are relatively dark and horizontal; They are puffy white or light gray clouds that look like floating cotton balls; They are generally about one kilometer wide which is about the size of your fist or larger when you hold up your hand at arm's length to look at the cloud.

Composition: Primarily of water droplets

Sunlight: Cannot see sun if covered

Weather Indications: "Fair weather clouds";  Over land cumulus develops on days of clear skies, and is due diurnal convection; it appears in the morning, grows, and then more or less dissolves again toward evening. Watch for rain showers when the cloud’s tops look like cauliflower heads.

5

Cirrocumulus "Mackeral Sky"

Origin:  from Cirrus (Latin: curl, tuft, fringe) + Cumulus (Latin: mass, pile)

Altitude: High (>7000 m)

Discription: Thin, white patch, sheet, or layered of clouds without shading. They are composed of very small elements in the form of more or less regularly arranged grains or ripples. They are the same size or smaller than the width of your littlest finger when you hold up your hand at arm's length. 

Compositon: Ice Crystals

Weather Indications:  Cirrocumulus are common in winter and indicate fair, but cold, weather.

 

6

Stratus

Origin: from Stratum (Latin: covering)

Altitude: Low (<2000 m)

Description: Uniform grayish, Covers entire sky; A generally gray cloud layer with a uniform base, often when a layer of Stratus breaks up and dissipates blue sky is seen; Stratus clouds can look like a fog that doesn't reach the ground. 

Composition: Primarily of water droplets

Sunlight: When the sun is visible through this cloud, its outline is clearly discernible.

Weather Indications:  Sometimes light mist or drizzle

7

Altocumulus

Origin:  from Altus (Latin: high) + Cumulus (Latin: mass, pile)

Altitude: Middle (7000m>2000 m)

Discription: One part of cloud darker than another. White and/or gray patch, sheet or layered clouds, generally composed of laminae (plates), rounded masses or rolls. They may be partly fibrous or diffuse.  Altocumulus clouds usually form in groups and are about one kilometer thick. Altocumulus clouds are about as wide as your thumb when you hold up your hand at arm's length. 

Compositon: Chiefly consist of super-cooled water droplets of minus 10C, but ice crystals are often present. 

Sunlight: When the edge or a thin semitransparent patch of altocumulus passes in front of the sun or moon a corona appears. This colored ring has red on the outside and blue inside and occurs within a few degrees of the sun or moon.

Weather Indications:  If in the morning, often thunderstorms by late afternoon as it shows instability and convection in the middle levels of the troposphere, the area where towering cumulus clouds can turn into cumulonimbus.

Possibel Confusion: Similar to cirrocumulus, but individual segments are larger and darker.

8

Cirrocumulus "Mackeral Sky"

Origin:  from Cirrus (Latin: curl, tuft, fringe) + Cumulus (Latin: mass, pile)

Altitude: High (>7000 m)

Discription: Thin, white patch, sheet, or layered of clouds without shading. They are composed of very small elements in the form of more or less regularly arranged grains or ripples. They are the same size or smaller than the width of your littlest finger when you hold up your hand at arm's length. 

Compositon: Ice Crystals

Weather Indications:  Cirrocumulus are common in winter and indicate fair, but cold, weather.

 

9

Cumulonimbus

Origin: Cumulus (Latin: mass, pile) + Nimbus (Latin: rainstorm)

Altitude: Low (<2000 m) building up vertically

Description: A heavy and dense cloud in the form of a mountain or huge tower. The upper portion is usually smoothed by wind, fibrous or striated and nearly always flattened in the shape of an anvil or vast plume. Under the base of this cloud which is often very dark, there are often low ragged clouds that may or may not merge with the base. 

Composition: Water droplets at base to ice at top

Sunlight: Cannot see sun if covered

Weather Indications: Produce heavy precipitation, which sometimes is in the form of virga, Lighting and thunder. Cumulonimbus clouds also produce hail and tornadoes. In winter, snow.

10

Stratocumulus

Origin: from Stratum (Latin: covering) + Cumulus (Latin: mass, pile)

Altitude: Low (<2000 m)

Description: Low, Lumpy; Gray or whitish patch, sheet, or layered clouds which almost always have dark tessellations (honeycomb appearance), rounded masses or rolls. Except for virga they are non-fibrous and may or may not be merged. They also have regularly arranged small elements with an apparent width of more than five degrees (three fingers - at arm's length). Sometimes they line up in rows and other times they spread out. 

Composition: Primarily of water droplets

Sunlight: Cannot see sun if covered

Weather Indications:  Only light rain (usually drizzle) falls from stratocumulus clouds. 

Possible Confusion:  To distinguish between a stratocumulus and an altocumulus cloud, point your hand toward the cloud. If the cloud is about the size of your fist, then it is stratocumulus.

11

Nimbostratus

Origin:  from Nimbus (Latin: rainstorm) + Stratum (Latin: covering)

Altitude: Low (<2000 m)

Description: Dark Gray, have ragged bases and sit low in the sky.

Composition: Primarily of water droplets

Sunlight: Cannot see sun

Weather Indications: The continuous rain cloud. Precipitation light to moderate; long duration

Possible Confusion: The sun (or moon) is not visible through nimbostratus clouds, which distinguishes them from mid-level altostratus clouds. 

12

Altostratus

Origin:  from Altus (Latin: high) + Stratum (Latin: covering)

Altitude: Middle (7000m>2000 m)

Description: Gray or bluish cloud sheets or layers of striated or fibrous clouds that totally or partially covers the sky. 

Composition: Altostratus may be composed of ice crystals. In some ice crystal altostratus, very thin, rapidly disappearing horizontal sheets of water droplets appear at random. The sizes of the ice crystals in the cloud tended to increase as altitude decreased. However, close to the bottom of the cloud, the particles decreased in size again. 

Sunlight: "water sun"; They are thin enough to regularly reveal the sun as if seen through ground glass.

Weather Indications: Light snow or rain possible, often in the form of virga. If the precipitation increases in persistence and intensity, the altostratus cloud may thicken into nimbostratus.

13

Cumulus Congestus

Origin: Cumulus (Latin: mass, pile), Congestus (accumulating)

Altitude: Low (<2000 m)

Description: Detached, generally dense clouds and with sharp outlines that develop vertically in the form of rising mounds, domes or towers with bulging upper parts resembling a cauliflower; The sunlit parts of these clouds are mostly brilliant white while their bases are relatively dark and horizontal;

Composition: Primarily of water droplets

Sunlight: Cannot see sun if covered

Weather Indications: Often first sign of thunderstorms

14

Altocumulus

Origin:  from Altus (Latin: high) + Cumulus (Latin: mass, pile)

Altitude: Middle (7000m>2000 m)

Discription: One part of cloud darker than another. White and/or gray patch, sheet or layered clouds, generally composed of laminae (plates), rounded masses or rolls. They may be partly fibrous or diffuse.  Altocumulus clouds usually form in groups and are about one kilometer thick. Altocumulus clouds are about as wide as your thumb when you hold up your hand at arm's length. 

Compositon: Chiefly consist of super-cooled water droplets of minus 10C, but ice crystals are often present. 

Sunlight: When the edge or a thin semitransparent patch of altocumulus passes in front of the sun or moon a corona appears. This colored ring has red on the outside and blue inside and occurs within a few degrees of the sun or moon.

Weather Indications:  If in the morning, often thunderstorms by late afternoon as it shows instability and convection in the middle levels of the troposphere, the area where towering cumulus clouds can turn into cumulonimbus.

Possibel Confusion: Similar to cirrocumulus, but individual segments are larger and darker.

15

Stratus

Origin: from Stratum (Latin: covering)

Altitude: Low (<2000 m)

Description: Uniform grayish, Covers entire sky; A generally gray cloud layer with a uniform base, often when a layer of Stratus breaks up and dissipates blue sky is seen; Stratus clouds can look like a fog that doesn't reach the ground. 

Composition: Primarily of water droplets

Sunlight: When the sun is visible through this cloud, its outline is clearly discernible.

Weather Indications:  Sometimes light mist or drizzle

16

Stratus

Origin: from Stratum (Latin: covering)

Altitude: Low (<2000 m)

Description: Uniform grayish, Covers entire sky; A generally gray cloud layer with a uniform base, often when a layer of Stratus breaks up and dissipates blue sky is seen; Stratus clouds can look like a fog that doesn't reach the ground. 

Composition: Primarily of water droplets

Sunlight: When the sun is visible through this cloud, its outline is clearly discernible.

Weather Indications:  Sometimes light mist or drizzle

17

Nimbostratus

Origin:  from Nimbus (Latin: rainstorm) + Stratum (Latin: covering)

Altitude: Low (<2000 m)

Description: Dark Gray, have ragged bases and sit low in the sky.

Composition: Primarily of water droplets

Sunlight: Cannot see sun

Weather Indications: The continuous rain cloud. Precipitation light to moderate; long duration

Possible Confusion: The sun (or moon) is not visible through nimbostratus clouds, which distinguishes them from mid-level altostratus clouds. 

18

Stratocumulus

Origin: from Stratum (Latin: covering) + Cumulus (Latin: mass, pile)

Altitude: Low (<2000 m)

Description: Low, Lumpy; Gray or whitish patch, sheet, or layered clouds which almost always have dark tessellations (honeycomb appearance), rounded masses or rolls. Except for virga they are non-fibrous and may or may not be merged. They also have regularly arranged small elements with an apparent width of more than five degrees (three fingers - at arm's length). Sometimes they line up in rows and other times they spread out. 

Composition: Primarily of water droplets

Sunlight: Cannot see sun if covered

Weather Indications:  Only light rain (usually drizzle) falls from stratocumulus clouds. 

Possible Confusion:  To distinguish between a stratocumulus and an altocumulus cloud, point your hand toward the cloud. If the cloud is about the size of your fist, then it is stratocumulus.

19

Nimbostratus

Origin:  from Nimbus (Latin: rainstorm) + Stratum (Latin: covering)

Altitude: Low (<2000 m)

Description: Dark Gray, have ragged bases and sit low in the sky.

Composition: Primarily of water droplets

Sunlight: Cannot see sun

Weather Indications: The continuous rain cloud. Precipitation light to moderate; long duration

Possible Confusion: The sun (or moon) is not visible through nimbostratus clouds, which distinguishes them from mid-level altostratus clouds. 

20

Cirrocumulus "Mackeral Sky"

Origin:  from Cirrus (Latin: curl, tuft, fringe) + Cumulus (Latin: mass, pile)

Altitude: High (>7000 m)

Discription: Thin, white patch, sheet, or layered of clouds without shading. They are composed of very small elements in the form of more or less regularly arranged grains or ripples. They are the same size or smaller than the width of your littlest finger when you hold up your hand at arm's length. 

Compositon: Ice Crystals

Weather Indications:  Cirrocumulus are common in winter and indicate fair, but cold, weather.

 

21

Altostratus

Origin:  from Altus (Latin: high) + Stratum (Latin: covering)

Altitude: Middle (7000m>2000 m)

Description: Gray or bluish cloud sheets or layers of striated or fibrous clouds that totally or partially covers the sky. 

Composition: Altostratus may be composed of ice crystals. In some ice crystal altostratus, very thin, rapidly disappearing horizontal sheets of water droplets appear at random. The sizes of the ice crystals in the cloud tended to increase as altitude decreased. However, close to the bottom of the cloud, the particles decreased in size again. 

Sunlight: "water sun"; They are thin enough to regularly reveal the sun as if seen through ground glass.

Weather Indications: Light snow or rain possible, often in the form of virga. If the precipitation increases in persistence and intensity, the altostratus cloud may thicken into nimbostratus.

22

Stratocumulus

Origin: from Stratum (Latin: covering) + Cumulus (Latin: mass, pile)

Altitude: Low (<2000 m)

Description: Low, Lumpy; Gray or whitish patch, sheet, or layered clouds which almost always have dark tessellations (honeycomb appearance), rounded masses or rolls. Except for virga they are non-fibrous and may or may not be merged. They also have regularly arranged small elements with an apparent width of more than five degrees (three fingers - at arm's length). Sometimes they line up in rows and other times they spread out. 

Composition: Primarily of water droplets

Sunlight: Cannot see sun if covered

Weather Indications:  Only light rain (usually drizzle) falls from stratocumulus clouds. 

Possible Confusion:  To distinguish between a stratocumulus and an altocumulus cloud, point your hand toward the cloud. If the cloud is about the size of your fist, then it is stratocumulus.

23

Cirrocumulus "Mackeral Sky"

Origin:  from Cirrus (Latin: curl, tuft, fringe) + Cumulus (Latin: mass, pile)

Altitude: High (>7000 m)

Discription: Thin, white patch, sheet, or layered of clouds without shading. They are composed of very small elements in the form of more or less regularly arranged grains or ripples. They are the same size or smaller than the width of your littlest finger when you hold up your hand at arm's length. 

Compositon: Ice Crystals

Weather Indications:  Cirrocumulus are common in winter and indicate fair, but cold, weather.

 

24

Altostratus

Origin:  from Altus (Latin: high) + Stratum (Latin: covering)

Altitude: Middle (7000m>2000 m)

Description: Gray or bluish cloud sheets or layers of striated or fibrous clouds that totally or partially covers the sky. 

Composition: Altostratus may be composed of ice crystals. In some ice crystal altostratus, very thin, rapidly disappearing horizontal sheets of water droplets appear at random. The sizes of the ice crystals in the cloud tended to increase as altitude decreased. However, close to the bottom of the cloud, the particles decreased in size again. 

Sunlight: "water sun"; They are thin enough to regularly reveal the sun as if seen through ground glass.

Weather Indications: Light snow or rain possible, often in the form of virga. If the precipitation increases in persistence and intensity, the altostratus cloud may thicken into nimbostratus.

25

Stratocumulus

Origin: from Stratum (Latin: covering) + Cumulus (Latin: mass, pile)

Altitude: Low (<2000 m)

Description: Low, Lumpy; Gray or whitish patch, sheet, or layered clouds which almost always have dark tessellations (honeycomb appearance), rounded masses or rolls. Except for virga they are non-fibrous and may or may not be merged. They also have regularly arranged small elements with an apparent width of more than five degrees (three fingers - at arm's length). Sometimes they line up in rows and other times they spread out. 

Composition: Primarily of water droplets

Sunlight: Cannot see sun if covered

Weather Indications:  Only light rain (usually drizzle) falls from stratocumulus clouds. 

Possible Confusion:  To distinguish between a stratocumulus and an altocumulus cloud, point your hand toward the cloud. If the cloud is about the size of your fist, then it is stratocumulus.

26

Cirrostratus

Origin:  from Cirrus (Latin: curl, tuft, fringe) + Stratum (Latin: a covering)

Altitude: High (>7000 m)

Discription: Transparent, whitish veil clouds with a fibrous (hair-like) or smooth appearance. A sheet of cirrostratus which is very extensive, nearly always ends by covering the whole sky.

Compositon: Ice Crystals

Sunlight: Produces an halo around the sun or moon.

Weather Indications:  Usually come 12 to 24 hours before a rain or snowstorm

Possible Confusion: A milky veil of fog (or thin Stratus) is distinguished from a veil of Cirrostratus of a similar appearance by the halo phenomena which the sun or the moon nearly always produces in a layer of cirrostratus. The halo is the width of your hand held at arm's length.

 

27

Cumulonimbus

Origin: Cumulus (Latin: mass, pile) + Nimbus (Latin: rainstorm)

Altitude: Low (<2000 m) building up vertically

Description: A heavy and dense cloud in the form of a mountain or huge tower. The upper portion is usually smoothed by wind, fibrous or striated and nearly always flattened in the shape of an anvil or vast plume. Under the base of this cloud which is often very dark, there are often low ragged clouds that may or may not merge with the base. 

Composition: Water droplets at base to ice at top

Sunlight: Cannot see sun if covered

Weather Indications: Produce heavy precipitation, which sometimes is in the form of virga, Lighting and thunder. Cumulonimbus clouds also produce hail and tornadoes. In winter, snow.

28

Altostratus

Origin:  from Altus (Latin: high) + Stratum (Latin: covering)

Altitude: Middle (7000m>2000 m)

Description: Gray or bluish cloud sheets or layers of striated or fibrous clouds that totally or partially covers the sky. 

Composition: Altostratus may be composed of ice crystals. In some ice crystal altostratus, very thin, rapidly disappearing horizontal sheets of water droplets appear at random. The sizes of the ice crystals in the cloud tended to increase as altitude decreased. However, close to the bottom of the cloud, the particles decreased in size again. 

Sunlight: "water sun"; They are thin enough to regularly reveal the sun as if seen through ground glass.

Weather Indications: Light snow or rain possible, often in the form of virga. If the precipitation increases in persistence and intensity, the altostratus cloud may thicken into nimbostratus.

29

Altocumulus

Origin:  from Altus (Latin: high) + Cumulus (Latin: mass, pile)

Altitude: Middle (7000m>2000 m)

Discription: One part of cloud darker than another. White and/or gray patch, sheet or layered clouds, generally composed of laminae (plates), rounded masses or rolls. They may be partly fibrous or diffuse.  Altocumulus clouds usually form in groups and are about one kilometer thick. Altocumulus clouds are about as wide as your thumb when you hold up your hand at arm's length. 

Compositon: Chiefly consist of super-cooled water droplets of minus 10C, but ice crystals are often present. 

Sunlight: When the edge or a thin semitransparent patch of altocumulus passes in front of the sun or moon a corona appears. This colored ring has red on the outside and blue inside and occurs within a few degrees of the sun or moon.

Weather Indications:  If in the morning, often thunderstorms by late afternoon as it shows instability and convection in the middle levels of the troposphere, the area where towering cumulus clouds can turn into cumulonimbus.

Possibel Confusion: Similar to cirrocumulus, but individual segments are larger and darker.

30

Cirrostratus

Origin:  from Cirrus (Latin: curl, tuft, fringe) + Stratum (Latin: a covering)

Altitude: High (>7000 m)

Discription: Transparent, whitish veil clouds with a fibrous (hair-like) or smooth appearance. A sheet of cirrostratus which is very extensive, nearly always ends by covering the whole sky.

Compositon: Ice Crystals

Sunlight: Produces an halo around the sun or moon.

Weather Indications:  Usually come 12 to 24 hours before a rain or snowstorm

Possible Confusion: A milky veil of fog (or thin Stratus) is distinguished from a veil of Cirrostratus of a similar appearance by the halo phenomena which the sun or the moon nearly always produces in a layer of cirrostratus. The halo is the width of your hand held at arm's length.