WV Enhancement

The WV curve is used for the 6.7 micron water vapor channel (CH3) on GOES.  The only
temperature range that is enhanced is between -10C and -60C.  This is the most important
range because it shows middle and upper tropospheric moisture patterns that relate to significant
features such as: jet streams, upper troughs, dry slots, and deformation zones.  Temperatures
colder than -60C are shown as white, and temperatures warmer than -10C are displayed as black. 
The latter condition is very rare, and occurs mainly in the subtropics.
