Geography: Weather, Climate, And Landscape

Front 1

CCNs

Back 1

hygroscopic: initiate condensation
hydrophobic: retard condensation
ice-forming nuclei freeing nuclei and sublimation nuclei

Front 2

Radiational Cooling

Back 2

CLEAR and CALM
NE in Fall
later afternoon Tdew is reasonable estimate of next morning's Tmin

Front 3

Radiation/Ground Fog

Back 3

clear night
high humidity at low elevations
light winds
hilly areas

Front 4

Advection Fog

Back 4

winter
moist air moves over a cooler surface
warm air to cold ground

Front 5

Steam Fog (Sea Smoke)

Back 5

warm water
cold air over water
condensation and fog forms

Front 6

Cumulus Congestus or TCU

Back 6

orographic ascent up over green mountains
bubbling appearance

Front 7

Orographic Towering Cumulus

Back 7

line of towering cumulus over spine of green mountains
FLAT BASES at lifted condensation level
building clouds are following by rain shafts and virga

Front 8

Cirrus

Back 8

HIGH
thing/fine base
angel hair

Front 9

Cirrocumulus

Back 9

HIGH
bright
size of thumb
puffy/pure ice

Front 10

Cirrostratus

Back 10

halo around sun
bright/looks like sheet

Front 11

Altostratus

Back 11

MIDDLE
dim sun
sun looks like pin prick of light

Front 12

Altocumulus

Back 12

MIDDLE
fist size
bumpy
darker, larger, lower

Front 13

Stratus

Back 13

LOW
closest
not doing anything
pancake

Front 14

Stratocumulus

Back 14

LOW
bumps
long flat base
in between cumulus and stratus

Front 15

Cumulus

Back 15

LOW
low
puffy

Front 16

Nimbostratus

Back 16

ALL HEIGHTS
RAIN OR SNOW PRODUCING
gray and raining all day

Front 17

Cumulonimbus

Back 17

ALL HEIGHTS
RAIN OR SNOW PRODUCING
thunderstorms, lightning, hail,
rain for hour and then stop, never all day

Front 18

Collision-Coalescence

Back 18

WARM CLOUDS
large droplets fall
attach to smaller droplets
grow then break apart because unstable
bigger now so fall even faster

Front 19

Bergeron Process

Back 19

COLD CLOUDS
ice crystal in midst of supercooled liquid water
saturated for liquid, supersaturated for ice crystals
ice crystals grow and water drops shrink
WATER VAPOR PRESSURE transfers water from drops to ice crystal

Front 20

Rain

Back 20

snow falls into warm air

Front 21

Freezing Rain

Back 21

snow melts, hits cold air, freezes when it hits something

not enough time to refreeze in air

Front 22

Sleet

Back 22

Snow melts, refreezes into sleet as it travels through cold air

Front 23

Snow

Back 23

Falling into cold air, never melts on way down

Front 24

Thunderstorm Ingredients and When

Back 24

1. warm air rising in an unstable environment

2. upper level diverging winds to draw air upwards

WHEN? spring and summer, afternoon and evening

Front 25

Airmass/Ordinary

Back 25

SINGLE CELL
develop in warm humid air away from fronts
short lived
rarely produce strong winds and large hail
3 stages: CUMULUS, MATURE, DISSIPATING
downdrafts bring cooling air

Front 26

Severe

Back 26

large hail, tornadoes, flash floods
ingredients:
moist unstable air rising
strong vertical wind shear (upper level winds)
long-lasting
supercell and squall line

Front 27

Squall Line

Back 27

multi-cell
continuous gust front along leading edge

Front 28

Super Cell

Back 28

rotate
long-lived
tends to be separated from other thunderstorms
rain free base
wall cloud - strongest updraft
large hail
mesocyclone
THUNDERSTORMS

Front 29

Tornadoes - Best Conditions

Back 29

rotating severe thunderstorms
unstable air
high humidity and dew point
upper level divergence in jet stream
near intense cold fronts and squall lines

Front 30

Tornadoes - How?

Back 30

Directional wind shear with height
cyclonic rotation of updraft (mesocyclone)
mesocyclone shrinks horizontally and stretches vertically
increase in speed of spinning air

Front 31

Hurricanes - Ingredients

Back 31

over tropical ocean (79 or warmer)
source of latent heat
none poleward of 20 degrees

Front 32

Hurricanes - How?

Back 32

light winds
deep layer of very humid air
CONVERGENCE of surface winds
strong Coriolis Force

Front 33

Hurricane Stages and Eye

Back 33

1. Tropical Disturbance
2. Tropical Depression
3. Tropical Storm
4. Hurricane

eye: no rain
scattered mid and high clouds
lowest pressure

eye wall: strongest winds, thickest cloud cover, most intense precipitation

smaller the eye, the more intense it is

Front 34

cP Modification

Back 34

cold, dense air, stable, moves from source
steam fog forms because crosses warm water
warms, moistens, and becomes unstable
produces precipitation on leeward banks

Front 35

mP Modification

Back 35

forms Chinook winds
west to east
modified, dry pacific air leeward side of Rocky
all rained out by time hits east of rockies

Front 36

Cold Front

Back 36

TRIANGLES
sharp temperature changes
shift in wind direction and pressure
steep noise
fast moving fronts - squall line with thunderstorms

Front 37

Warm Front

Back 37

SEMI CIRCLES
warm, moist air replaces retreating cold air
half the speed of cold air
overrunning: warm air rises over cold - clouds and precipitation ahead of front

Front 38

Stationary Front

Back 38

OPPOSING DIRECTIONS OF CIRCLES & TRIANGLES
air flow parallel to the boundary
stalling
associated with FLOODING

Front 39

Occluded Front

Back 39

SAME DIRECTION OF CIRCLES & TRIANGLES
cold front catches up and overtakes a warm one
Cold occlusion: colder air behind front
Warm occlusion: milder air behind front