Download Types of Clouds

Types of Clouds
Cirrus, Stratus, Cumulus and
Cumulonimbus
What causes clouds to form?
 There must be three main ingredients present in order for clouds to
form:
1. Moisture - There must be sufficient water vapor in the air to build a
cloud.
2. Cooling air - The air temperature must decrease enough for water vapor
to condense and form droplets.
3. Condensation nuclei - Tiny particles, invisible to the human eye, such
as dust, dirt, and pollutants, provide surfaces on which water molecules
can gather and condense into water droplets.
 If the conditions are right, then a cloud will form. Clouds often form
where two weather fronts meet, like when a cold front meets a warm
front. The kind of clouds that form can say a lot about what type of
weather is coming! The main kinds of clouds are stratus, cumulus, and
cirrus clouds, and each one forms under different conditions.
Cirrus Clouds
•Cirrus is a Latin word that means “curl of hair”.
•Typically found at high altitudes.
•Thin wispy clouds
•Cirrus clouds are composed of ice crystals that originate from the
freezing of super cooled water droplets.
• Cirrus generally occur in fair weather and point in the direction of
air movement at their elevation.
Stratus Clouds
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The word stratus comes from Latin, means “to spread out”.
Stratus clouds are usually low clouds seen on an overcast day.
Stratus clouds often block out the sun.
Usually produce light to heavy continuous rain.
Fog can be considered a low stratus cloud in contact with the ground. When the
fog lifts, it usually becomes true stratus.
Cumulus Clouds
• The word cumulus comes from Latin, “means heap or pile”.
• Cumulus clouds are usually puffy with distinct edges and usually a
noticeable vertical (upward) development.
• Cumulus clouds are sometimes associated with
thunderstorms.
Cumulonimbus Clouds
• These clouds are named because they are puffy
("cumulo") and because they often are dark clouds
which cause rainstorms ("nimbus").
• Cumulonimbus clouds are different because they
cannot be classified as low, middle or high altitude
clouds.
• These are often storm clouds which can be ten or
more miles in height, extending through all the levels
of altitude.
• These clouds form when a front of cool air meets a
body of hot, moist air.
• Cumulonimbus clouds can produce rain showers,
snow showers, hail, or even thunderstorms
Cumulonimbus