Weather Quiz 4 Flashcards
Advection Fog
moist air over cold surface
wind direction important
deepens with wind up to 15kts
could be warm air over cold water (san Fransisco)
upslope fog
moist, stable air lifted and adiabatically cooled up sloping terrain
common in early morning
5-15kt wind
Steam fog
cold air over warm water
water evaporates then condenses with convective air
needs shallow layer of unstable air
mist
if visibility is +1000m
5/8 to 7 mile visibility
haze
suspension of small, dry particles
radiation fog
radiation cooling reduces air to dew point
shallow fog
depends with wind up to 5kts
frontal fog
warm air lifted over front
common with warm front
sea breeze
coastal local wind
Sea to land
calm sunny, summer days
land heats faster than water - warm air rises and lower colder air moves in
land breeze
land to sea
develop in PGF
weaker than sea breeze
reverse of sea breeze
Lake breeze
in afternoon, spring/summer
shallow end less effective than deep end
valley breeze
wind ascends mountain during day
air touching mountain heats faster
creates low pressure pushing wind valley to upward
mountain breeze
nightly downslope winds
air on mountain cools faster
when will radiation fog form (time of day)
overnight or early morning
most common type of fog
radiation fog
clockwise wind
veering wind
backing wind
counterclockwise wind
diurnal variation
winds stronger during day
winds aloft can be transferred to surface in instability
Where does CAT normally exist
sharp upper trough or sharp upper ridge of jet stream
Northern portion of surface low
dew point depression for haze
greater than 3F
what causes blowing sand / dust
thunderstorm outflows
strong pressure gradients
signs of flying through ash
thunder and lightning
St Elmo’s fire
chinook winds
downsloping winds warm on descent
santa ana winds
downslope winds are warm and hot
get funneled through mountain passes
turbulence along thunderstorm is
moderate or severe
