Term
| Radiation Fog – AKA? When does it develop? |
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Definition
Radiation (aka Ground) Fog Develops with...
Warm, Moist air…
Over Low, Flatland areas…
On Clear, Calm nights. |
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Term
| Advection Fog - When does it develop? |
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Definition
Remember “AD” as in Latin for “to” and “VECTION” as in Latin’s “veher” (to carry) – i.e. carry from the sea to land.
Develops when warm air moves over a cold surface, specifically when a warm air mass moves inland from the coast, in winter |
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Term
| Steam Fog - When does it develop? What hazards might this create? |
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Definition
Typical in the arctic, over water that’s relatively warm compared to the air above.
Hazards of…
Low level turbulence
Icing. |
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Term
| Stratus clouds form under in what conditions? |
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Definition
Stable air.
When a layer of STABLE, warm, moist air rises, expands, and cools down. |
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Term
| “Nimbus” in a cloud’s name indicates… |
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Definition
| A rain cloud (be it stratus, cumulus, etc). |
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Term
| Cumulus clouds require what to form… |
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Definition
Think of cuMULus…
M Moist air
U Unstable air
L Lifting force |
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Term
| Towering cumulus clouds indicate… |
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Definition
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Term
| Thunderstorm development stages – the names and characteristics… |
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Definition
Cumulus stage – Continuous updrafts
Mature stage –
Updrafts AND downdrafts.
Precipitation begins.
Greatest intensity
Dissipating stage – Mostly downdrafts. |
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Term
Cumulonimbus Mamma clouds are associated with what?
They have an appearance including… |
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Definition
Violent thunderstorms and tornadoes
Have irregular, udder-shaped bottoms. |
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Term
| Clouds that crest mountains and appear to be stationary are known as what? What do they signify? |
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Definition
Lens-shaped Standing Lenticular Clouds
Signify strong winds. |
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Term
| Cloud “ceilings” include __, but not ___... |
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Definition
| Lowest layer of clouds either BROKEN or OVERCAST, but NOT SCATTERED or FEW |
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Term
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Definition
| Temperature to which the air must be cooled in order to become saturated. |
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Term
| If the temperature / dewpoint spread is small and decreasing, and the air temp is in the 60s F, what type of weather is most likely to develop? |
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Definition
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Term
| Clouds, Fog, or Dew form when… |
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Definition
| They will always form when water vapor condenses. |
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Term
Height of a cumulus cloud is determined by what?
What about the rate?
How to calculate? |
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Definition
The height is determined by the spread between the temperature and the dewpoint. Those two converge with altitude, normally at a rate of rate of 4.4F (2.5C)/ 1,000’
Calculate in an order suggested by mnemonic SDM – StaDiuM…
1) S Subtract the dewpoint from the temperature
2) D Divide the spread by 4.4 if in F (or 2.5 if in Celsius)
3) M Multiply by 1000’
4) If needed, add the above result to the field elevation for the cloud’s altitude in MSL. |
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