Understanding Weather
Carin Miranda
Smyrna Middle School
Winter 2013
Water in the Air
• Evaporation is when water changes from a
liquid to a gas.
• When air reaches its dew point relative
humidity is at 100%
Clouds
• Nimbostratus clouds will bring light to
heavy continuous rainy weather.
• Cumulonimbus clouds are large
thunderstorm clouds that produce
precipitation.
• Altocumulus clouds are puffy mid-level
clouds.
• Cirrus clouds are high clouds made of ice
crystals.
Precipitation
• Sleet-Starts as rain then freezes in the
air.
• Snow-Water vapor changes directly
into a solid because of cold
temperatures.
• Hail-Forms when precipitation is sent
back up into the clouds many times.
Air Masses
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Continental polar (cP) dry and cold
Maritime polar (mP) wet and cold
Continental tropical (cT) dry and warm
Maritime tropical (mT) wet and warm
C=dry
P=cold
M=wet
t-=warm
Fronts
• Warm front-warm air moves over cold air and
replaces it.
• Stationary front-Not moving. Brings many days of
cloudy, wet weather.
• Cold front-cold air mass displaces a warm air
mass.
• Occluded front-warm air mass is caught between
two cold air masses and is forced to rise. Lots of
precipitation.
Meteorology
• Images of weather systems on television
come from weather satellites.
• From a weather map you can tell the
locations of cold and warm fronts.
• The lines connecting points of equal
pressure on weather maps are called isobars.
• Isobars help meteorologists by showing
areas of high and low pressure.
Vocabulary
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Humidity
Air mass
Front
Barometric pressure
Meteorologist
Psychrometer
Vocabulary 2
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Thermometer
Barometer
Anemometer
Rain Gauge
Wind Vane
Wind
Vocabulary 3
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Hygrometer
Weather
Relative Humidity
Condensation
Cloud
Precipitation