Cloud, Precipitation, &
Storm Formation
Cloud Formation
1) Clouds form as warm
air is forced upward from
evaporation
2) As the air is forced
upward, it expands and
cools
3) As the air cools, it
condenses around solid
particles of dust, pollen,
& pollution
4) Cloud Forms
Cloud Types
Cloud Type
Classification
Clouds are classified based on:
1) Shape
2) Height
3) Rain Capacity
Shape
Stratus
Cirrus
Cumulus
Stratus Clouds
-Stratus clouds form a
smooth, even sheet
-They usually form at
low altitudes
-When water vapor is
super condensed,
stratus clouds form fog
*Strato- prefix for low lying clouds below 2000m
Cirrus Clouds
-Cirrus clouds are
high, thin, white,
feathery clouds
containing ice
crystals
-Associated with
fair weather
*Cirro- prefix for clouds above 6000m
Cumulus Clouds
-Masses of puffy,
white clouds, often
with flat bases
-Form when air
currents rise
-Associated with fair
weather and
thunderstorms then
usually referred to as
cumulonimbus
Thunderstorms
Air Mass- large body of air
with the same temperature,
pressure, and humidity
Cold and Warm Air Massesproduced when air remains
over an area for a long time
Warm air rises while cold air
falls. When a storm occurs,
warm air is overtaken by cold
air
Hurricanes
Bodies of water are able to
hold more warmth allowing for
easy storm formation
All of this occurs because of…
Convection
Currents
Forms of
Precipitation
Types of
Precipitation
Precipitation form of water that
falls to the Earth's
surface.
Depends upon
the formation
process and the
temperatures of
the environment
between the
cloud and the
surface
Rain
Rain develops
when growing
cloud droplets
become too
heavy to remain
in the cloud and
as a result, fall
toward the
surface as rain
Rain usually
begins as ice
crystals- snow
This snow thaws
as it passes
through warmer
temps in the
atmosphere
Hail
Hail is formed when
updrafts carry
raindrops upwards
into extremely cold
areas of the
atmosphere
The raindrops
merge and freeze
to form hail
Sleet
Sleet is frozen
raindrops
Sleet begins as
snow hits warm air
to turn to rain then
falls through cold
air next to the
surface causing
freezing
Freezing Rain
Freezing rain is
falling rain that
cools below
0°C, but does
not turn to ice in
the air