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

Hurricanes
 
  introduction
 
  growth processes
 
> development stages
 
  movement
 
  public awareness
 
  public action
 
  damage
 
  names
 
  global activity
 
  el nino

Development Stages
 
  stages
 
  tropical depression
 
  tropical storm
 
> hurricanes

Hurricanes
 
  hurricanes
 
  eye
 
  eye wall
 
  spiral bands
 
> pres & wind

User Interface
 
  graphics
> text

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Pressure and Winds
the distribution across a hurricane

Atmospheric pressure and wind speed change across the diameter of a hurricane. To demonstrate, the diagram below shows a rough profile of wind speed (blue) and surface pressure (red) across a hurricane. Between 100 and 200 kilometers from the eye, the winds are fast enough to qualify as tropical storm force. The atmospheric pressure here will still be relatively high compared to the storm's center at about 990 to 1010 millibars. However, the pressure gradually falls and the wind speed rises upon getting closer to the eye wall. It is only over the last 50 to 100 kilometers that the large changes in pressure and wind speed occur.

[Image: (27K)]

The pressure begins to fall more rapidly while the wind speed simultaneously increases. Within the eye wall, the wind speed reaches its maximum but within the eye, the winds become very light ­ sometimes even calm. The surface pressure continues to drop through the eye wall and into the center of the eye, where the lowest pressure is found. Upon exiting the eye, the wind speed and pressure both increase rapidly. The wind speed again reaches a maximum in the opposite eye wall, and then quickly begins to decrease. The wind and pressure profiles inside a hurricane are roughly symmetrical, so a quick rise in winds and pressure through the eye wall followed by a slower increase in pressure and likewise decrease in wind speed would be expected.



spiral bands
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.

Hurricanes