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Activity 3
Tracking Thunderstorm Movement through Radar
Think About It Date
Page F88 Page
· How can you predict
how long a thunderstorm
will last?
· How do you know
when the danger of
severe weather has
passed?
Activity 3
Tracking Thunderstorm Movement through Radar
Investigate Date
Pages F89-90 Page
1a. Speculate on what
you think the blotches
near the radar location
represent.
2a. Which area has
the most intense
precipitation?
2b. How many levels
of precipitation intensity
does this area have?
2c. How far away is
this area from the radar
station?
2d. In which direction
is the area moving?
3a. How many levels
of intensity are now
indicated in the area
of most intense
precipitation?
3b. Describe how the
precipitation intensity
changed between 3 pm
and 4 pm.
4a. In which general
direction did the areas
of precipitation move
between 3 pm and 4pm?
Justify your answer
4b. What was the speed
of movement of the areas
of precipitation in
kilometers per hour?
Include a description of
the method you used to
determine the speed.
4c. Where do you expect
the areas to be located at
5 pm? Explain your answer.
4d. How do you explain
the distribution and
movement of the areas
of precipitation?
5a. How do you think
that radar detects
precipitation?
5b. How do you think
radar distinguishes heavy
versus light precipitation?
Activity 3
Tracking Thunderstorm Movement
through Radar
Digging Deeper Date
Pages F90-93 Page
Radar acronym for RAdio Detection And Ranging; it sends out and receives back pulses of microwave energy
To track precipitation, a radar unit sends out and receives pulses from precipitation targets
Rain, snow, or hail in the path of the radar beam reflects some of that energy back to the radar antenna
Radar echo the energy is electronically processed and appears as a color coded blotched on a computer screen
Echo strength is calibrated on a color scale with light green indicating light precipitation and dark red signaling heavy precipitation
Ground clutter echo on radar from tall buildings or smokestacks reflect radar signals
Thunderstorm cell is several kilometers or miles across and passes through the cumulus, mature and dissipating stages
Squall lines an elongated band of thunderstorm cells that last for several hours
They form in the warm humid air along or just ahead of a well-defined cold front
Mesoscale a nearly circular cluster of
convective thunderstorm cells covering an complex (MCC) area that may be a thousand times
that of an individual cell
Last for 12-24 hours
They are common at night during the warm season (March- September) over the eastern two-thirds of the US
Supercell a single thunderstorm cell that is much larger and longer-lasting than an ordinary cell
They are responsible for the most powerful tornadoes and the largest, most destructive hail
Activity 3
Tracking Thunderstorm Movement through Radar
Check Your Understanding Date
Page F93 Page
1. What man-made or
natural features could
interfere with weather
radar?
2. How would you
calculate the speed at
which a thunderstorm
cell is moving?
3. In your own words,
describe a squall line.
4. How could you
differentiate between
a supercell and an
ordinary thunderstorm
cell?
Activity 3
Tracking Thunderstorm Movement through Radar
Understanding and Applying Date
Page F93 Page
1. Explain why
thunderstorm weather
may persist at a
particular place for
many hours.
2. In what way does
a supercell thunderstorm
pose a greater hazard
than an ordinary
thunderstorm cell?
3a. How does that
predicted path of the
precipitation compare
with the actual path?
3b. How did the
predicted speed of
movement compare to
the actual speed of
movement?
c. Are the thunderstorm
cells weakening over
time or becoming
stronger? Explain.
Activity 3
Tracking Thunderstorm Movement through Radar
Inquiring Further Date
Page F94 Page
1. Investigating advances
in weather forecasting
Create a poster
presentation that explains
how Doppler radar differs
from the conventional
(reflection only) type of
weather radar. Consider
the following:
a. Describe in your
own words the
Doppler principle.
b. What can Doppler
radar do that
conventional radar
can’t?
c. How does Doppler
radar help forecasters
better predict severe
weather?
d. Is your community
covered by a National
Weather Service
Doppler radar?