MD Enhancement

The MD curve is a modification of the popular, general use MB enhancement scheme.  It is
intended for warm season use, and provides improved enhancement within the gray "step
wedges"  that depict "warm top" convection (Segment number 4, 5, 6).  An additional
improvement is better delineation of warm low clouds (30C to 7C).  The middle cloud range is
somewhat broader than the MB, and enhancement of details is minimized.   Otherwise, it is the
same as the MB curve.