WW2010
University of Illinois

WW2010
 
welcome
 
online guides
 
archives
 
educational cd-rom
 
current weather
 
about ww2010
 
index

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

Modeling
 
introduction
 
supercells
 
convective lines
 
forecasting

Supercells
 
introduction
 
structure
 
tornadoes

User Interface
 
graphics
text

.
Supercell Structure

Supercells have a common structure, as can be seen by the left diagram below. Computer model visualizations (below right) can capture most of this structure.

[Image: (32K)] [Image: (22K)] Image by NCSA/Wilhelmson
Click image for video (Must have RealPlayer G2)
Supercells are characteristically tall storms -- reaching way up into the stratosphere. The main updraft and downdraft mutually support one another leading to a long lasting storm. Click on the image below to explore a 3D severe storm through VRML.


Click to explore VRML Storm (11MB).
Click to explore VRML Storm.
Often, if you can see the whole storm, you can see a large dome above the central updraft and a broad, flat region covering the entire storm and extending downwind of the updraft. This is called the anvil, and both features show up well in this model. [Image: (22K)]
Image by NCSA/Wilhelmson
[Image: (27K)]
Image by NCSA/Wilhelmson 		Another characteristic observable in both models and in nature is the large cloud free area above the base of the updraft known as the vault or Weak Echo Region. Rain and possibly hail fall to the ground outside this region, leaving the vault region relatively precipitation-free.
In some supercells, one can sometimes observe both a v-notch and a hook echo. In this modeled radar image, both are evident. A hook echo is a strong signal that a supercell thunderstorm is about to or already has produced a tornado.
Image by NCSA/Wilhelmson

Click for VRML flanking line 		Some supercell thunderstorms also possess a clearly visible flanking line. The flanking line separates cool storm outflow from warm moist storm inflow and sits above the gust front. New storms form along the flanking line as the moist inflow air rises as it approaches the cool surface air. In this VRML environment, the blue body represents areas of significant cloud development with the flanking line very evident (foreground of image).
Weightless particles are used to trace the air motion within a supercell. Blue balls are sinking and orange balls are rising. [Image: (38K)]
Image by NCSA/Wilhelmson


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.

tornadoes