WW2010
University of Illinois

WW2010
 
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Online Guides
 
  introduction
 
> meteorology
 
  remote sensing
 
  reading maps
 
  projects, activities

Meteorology
 
  introduction
 
  air masses, fronts
 
  clouds, precipitation
 
  el nino
 
  forces, winds
 
  hurricanes
 
  hydrologic cycle
 
  light, optics
 
  midlatitude cyclones
 
> severe storms
 
  weather forecasting

Severe Storms
 
  introduction
 
  dangers of t-storms
 
  types of t-storms
 
> tstorm components
 
  tornadoes
 
  modeling

Tstorm Components
 
  introduction
 
  updrafts/downdrafts
 
  wind shear
 
> outflow phenomena
 
  wall clouds

Outflow Phenomena
 
  introduction
 
  gust fronts
 
> microbursts
 
  scud clouds, virga
 
  rain foot, dust foot

Microbursts
 
  introduction
 
> anatomy
 
  developing rain shaft
 
  extreme microburst

User Interface
 
  graphics
> text

NOTE: We've guessed that you're not using a client that supports colored tables and have tried to compensate. Low graphics mode looks much better on clients that do... we recommend switching to Netscape 3.0 or Microsoft Internet Explorer.
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Anatomy of Microbursts
and the dangers they pose to aircraft

The anatomy of a microburst shows that the highest wind speeds occur shortly after the cold air has impinged upon the ground. The spin-up of the microburst curl then results in an acceleration of wind velocities about the curl.

[Image: influence of microbursts on aircraft (72K)]

An aircraft entering a microburst will encounter strong headwinds, followed by strong tailwinds, as it flies from one side of the microburst to the other. If the pilot compensates for the headwind (to decrease lift) a bit too much, then the aircraft will lose lift in the tailwind and quickly strike the ground.

[Image: microburst producing storms (54K)] The end of microburst danger comes minutes after the air reaches ground, but other microbursts will follow in many cases, similar to repeated tornado events with a cyclic supercell. It was determined that one airliner crashed after it encountered three microbursts in rapid succession upon final approach.

Microbursts will occur with a plethora of thunderstorm types, even dissipating anvil clouds in some cases. The important message is that some thunderstorms or even weak convective showers which were regarded as harmless a few years ago are now recognized to be potential killers.



introduction
Terms for using data resources. CD-ROM available.
Credits and Acknowledgments for WW2010.
Department of Atmospheric Sciences (DAS) at
the University of Illinois at Urbana-Champaign.

developing rain shaft