Mechanics

gradient winds

result of pressure gradient force and coriolos force

flow perpendicular to the pressure gradient force and flows parallel to the isobars

clockwise around highs, counterclockwise around lows

found above 2,000 ft AGL

surface winds

move clockwise around highs and counterclockwise around lows but blows across isobars at a 45 deg angle and has component of motion that moves air out of the high pressure and into the low

found below 2,000 ft AGL

Buys Ballots Law

if the wind is at your back, the area of low pressure will be to your left

jet stream

narrow band of strong winds of 50 knots or more that meanders vertically and horizontally around the hemisphere in wave like patterns

sea breeze

when air above the land is hotter than the cold air over the ocea. the high pressure from the ocean moves towards the land creating winds replacing the warm air that moved upward

land breeze

circulation is reversed from sea breeze producing an offshore breeze

hydrological cycle

process in which moisture changes state as it moves throughout the atmosphere

cloud

condensed water vapor, consisting of water droplets or ice crystals

condensation nuclei

dust, salt crystals, acid salts, etc. that allow condensation to have a surface to condense on

two principal cloud forms

cumuliform

stratiform

cumuliform cloud

lumpy, billowy cloud with a base showing a definite pattern or structure

stratiform cloud

uniform base, formed in horizontal, sheet-like layers

low clouds

just above surface - 6500 ft AGL

no special prefix

mainly composed of water droplets and present serious hazard to flying

middle clouds

6500 ft - 20,000 ft AGL

composed of ice crystals, water droplets, or both and visibility depends on cloud density

prefix of alto

high clouds

20,000 - 40,000 ft AGL

prefix of cirro or cirrus

limited effect on flying except for moderate turbulence and limited visibility

special clouds with extensive vertical development

consists of towering cumulus and cumulonimbus clouds

bases found in low to middle cloud height and top extends to high cloud

three characteristics of precipitation

shower

continuous

internittent

4 methods of lifting

convergence

frontal

orographic

thermal

3 conditions of stability

stable, netural stable, unstable

front

area of discontinuity that forms between two contrasting air masses when they are adjacent to each other

discontinuities used to locate and classify fronts

temperature, moisture, winds, and pressure

cold front

leading edge of an advancing cold air mass

squall line

line of violent thunderstorms

warm front

boundary of the advancing warm air mass that is overtaking and replacing a colder air mass

rides up and over the top of a cold air mass

stationary front

neither air mass is replacing the other

occluded front

a faster moving cold front overtakes a slower moving warm front

two types: cold and warm

the type of occulsion depends on

whihc front remains in contact with the ground