which bounces off objects of certain size e.g., raindrops

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which bounces off objects of certain size (e.g.,
raindrops) and returns a signal
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US RADAR stations
http//www.srh.noaa.gov/bna/
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movement towards the RADAR intensifies the
return signal movement away from RADAR
decreases return signal
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Doppler RADAR
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Radial velocity mapshows relative movement of
rainfall,
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RADAR has shown that (RADAR images of the hook
are said to show a hook echo)
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Doppler RADAR
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Portable Doppler RADAR
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At the center of some large mesocyclones there
is an area of weak RADAR reflectivity. This
area is known as the
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BWERarea of low RADAR return signal is
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Since 1982, successful tornado forecasts have
increased and false alarms have declined. This
is due mainly to the advent of
Doppler RADAR in 1982
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(No Transcript)
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MYTH of TRUTH?

• Areas near lakes, rivers, and mountains are safe
• from tornadoes.

• Windows should be opened before a tornado
  approaches to
• equalize the pressure.

• If you are driving and a tornado is sighted, you
  should turn and drive
• at right angles to the storm.

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MYTH or TRUTH

• Large cities are not at danger from tornadoes

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Reduction in the number of tornado deaths after
1950 is attributed to 1) use of RADAR to
detect storms and issue warnings
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• Go to your pre-designated interior room, basement
• Stay away from windows
• Get out of cars
• Leave mobile homes and go to nearest sturdy
  shelter
• If caught outside in tornado, lay flat in a ditch
  or low spot

(flying debris is the cause of most tornado
deaths)
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Tornadoes preferentially kill

• The elderly
• Mobile home residents
• Occupants of exterior rooms with windows
• Those unaware of broadcast tornado warnings

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WATCHES AND WARNINGS
Tornado watchissued for producing
tornadoes time to stay tuned
for later forecasts
Tornado warningissued time
to seek safe shelter