Date post: | 19-Jan-2016 |
Category: |
Documents |
Upload: | angelina-heath |
View: | 215 times |
Download: | 0 times |
Mr. Hartwell -- F-M Meteorology
Cloud Types &Properties
Clouds• Formed when moist air is cooled
enough to allow saturation & condensation to take place.
• Saturation: air is completely filled with water vapor
• Condensation: phase change from gas to liquid
Clouds cont.
• Different types form based on:• Amount of moisture in the air• Vertical air temperature through troposphere• Character of rising air (speed & location)• Approaching weather systems
• Identified by:• Shape• Height• Composition• Character (puffy vs. layered)
Classification—Type #1• Cirrus —feathery, wispy, thin
Classification—Type #2
• Cumuliform —puffy, round, pretty
Classification—Type #3
• Stratiform —layered, sheet-like, strata=layers (like
rocks)
Classification—Type #4
• Nimbus —produces precipitation
Heights (HIGH): CIRRUS (Ci)
• Cirrus — made of ice crystals
• Align with upper level winds
• Indicate fair weather conditions
Aka: Mare’s Tails (look like horse’s tails)
Heights (HIGH): Cirrocumulus (Cc)
• Cirrocumulus — ice crystals
• Occur in moist & unstable air (aloft)
• Appear with precip.-causing weather (warm fronts)Aka: “Mackerel sky, not three days dry”
Heights (HIGH): Cirrostratus (Cs)
• Cirrostratus — ice crystals
• Common in winter with precip.-causing weather
• Produce sun dogs & halos
Sun Dog Halos
Heights (Middle) : Altocumulus (Ac)
• Occur in moist air that is lifting
• Fist-thumb-pinkeytip rule
• Altocumulus = thumb size
• Signals approaching storm system
Heights (Middle) : Altostratus (As)
• Layered; liquid water
• Gray to pale blue
• Occurs where moist air is rising slowly
• Just ahead of rainy weather
Heights (Low) : Cumulus (Cu)
• Puffy, white, pretty
• Indicates fair weather
• Well-defined bases
• Caused by humid air rising in bubbles
Heights (Low) : Cumulus Congestus
• Aka: towering cumulus
• Atmosphere is very unstable
• Indicates stormy conditions later in the day
Heights (Low) : Status (St)
• Sheet cloud; layers
• Hovers just above the ground (was fog?)
• No precip., but may be misty
Precipitating Clouds: Nimbostratus (Ns)
• Same as stratus, just precipitating
• Precedes warmth (occur before warm fronts)
Precipitating Clouds: Cumulonimbus (Cb)
• Thunderstorm!• Can poke into
stratosphere• Associated
with severe weather
• Anvil shape tops with mammatus clouds
Precipitating Clouds: Cumulonimbus (Cb)
Precipitating Clouds: Cumulonimbus (Cb)
Mammatus cloud (below)
Anvil shape (above)
Miscellaneous: Contrails
Miscellaneous: Fallstreaks
Formation: Sublimation of falling ice crystals carried by winds aloft