Download Fronts Reading

WHAT IS A FRONT?
Fronts = the boundaries between air masses
A front is defined as the transition zone
between two air masses! As an example in
the diagram below there is a front that exists
between the advancing cold air mass and the
retreating warm air mass. A cold front is
the LEADING edge of the cold air mass. A
warm front is the LEADING edge of a warm
air mass.
One thing to always remember:
Cold air is denser than warm air.
Colder air is always on the bottom
pushing around the warmer air up
and out of the way.
THERE ARE FOUR MAIN TYPES OF FRONTS: (Cold, Warm, Occluded, Stationary)
COLD FRONTS:
A cold front shows the advancement of cold air into
a region of warmer air. Interactions along the edge
of this front often results in showers and storms
developing, as the warmer air is pushed upward by
the advancing colder air. Usually the precipitation
will last only a few hours as the front passes
The air behind a cold front is noticeably colder and
drier than the air ahead of it. When a cold front
passes through, temperatures can drop more than 15
degrees within the first hour!
There is typically a noticeable
temperature change from one side of
a cold front to the other. In the map
of surface temperatures to the right,
the station east of the front reported a
temperature of 55 degrees Fahrenheit
while a short distance behind the
front, the temperature decreased to
38 degrees. An abrupt temperature
change over a short distance is a
good indicator that a front is located
somewhere in between.
Common characteristics associated with cold fronts have been listed in the table below.
Temperature
Pressure
Precipitation
Weather Change
From warm humid air to colder less
humid air
The air pressure steadily increases
Short Period of Showers while the
front is passing which could last about
2 to 3 hours
WARM FRONTS:
Warm Fronts are regions of warm air that
are advancing on colder air. Warm fronts
usually move more slowly than cold fronts.
Warm front usually have continual and
prolonged precipitation lasting several hours
or more. Warm fronts on a map are red and
have scalloped edges pointing towards the
cool air it's attempting to override.
When a warm front passes through, the air
becomes noticeably warmer and more
humid than it was before.
Weather Change
From cool temps to warmer temps
Temperature
Pressure
Precipitation
The air pressure steadily drops
Long Period of Showers while the
front is passing which could last up to
24 hours
STATIONARY FRONTS:
Stationary Fronts are pretty much just that:
Stationary. The two air masses just don’t
move. The weather along these fronts is
similar to warm fronts, less turbulent, but
often longer lasting.
Occluded Fronts are usually only seen in mature
cyclones, and they develop right around the same
time a storm system has peaked in strength and
will begin to weaken. Here onrushing cold air,
which is most dense and thus digs under all air
with warmer temperature, has at last elevated all
warm air ahead of it and has become separated
from a warm influx and is left with cool air in its
place. Warm air may still be fed into the system for energy, but it will be at points farther
and farther away from the beginning of the occlusion.
Questions
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What is a front?
What is an example of a front?
What is more dense cold, or warm air explain?
What type of weather does a cold front bring?
What is an indicator of where a front is located?
What type of weather does a warm front bring?
What happens at a stationary front, explain weather?
What happens at occluded front and what weather occurs there?