TINTXL    Exceptions list for vertical interpolation to potential temperature
           surfaces (*VPOT).  The list consists of up to 100 groups of values,
           with exactly 4 values per group.  The values in each group are as
           follows.

           1) field name (up to 8 CHARACTERS)

           2) interpolation type code (INTEGER)
              0 - no interpolation
              1 - linear in sigma
              2 - linear in natural log of sigma (default)
              3 - linear in natural log of natural log of (1000*sigma + 2.72)

           3) lower boundary treatment code (INTEGER)

              1 - use the surface level if available, extrapolate below the
                  surface if necessary
              2 - use the surface level if available, block points below ground
                  elevation
              3 - don't use the surface level, extrapolate below the lowest
                  free atmospheric level if necessary
              4 - don't use the surface level, block points below the lowest
                  free atmospheric level (default)

           4) number of Planetary Boundary Layer levels to copy without inter-
              polating (INTEGER).

              The default exceptions list, which is used if, and only if, all
           three of the ICPs <INTDT>, <LBTDT>, and <NLCDT> are defaulted, is
           given below.  If a value is input for any of these ICPs, the default
           exceptions list is null (i.e., there are no exceptions).

            TINTXL = 'Z'     ,2,1,0
                   , 'HT0'   ,2,1,0
                   , 'HT1'   ,2,1,0
                   , 'Q'     ,3,4,0
                   , 'MIXRAT',3,4,0
                   , 'MOIST' ,0,4,0
                   , 'CLD'   ,0,4,0
                   , 'CLOUD' ,0,4,0
                   , 'QC'    ,0,4,0
                   , 'QRS'   ,0,4,0
                   , 'QRL'   ,0,4,0
                   , 'DTCONV',0,4,0

            Example 1:
            LBTDT  =  3
            TINTXL = 'Z',2,1,0,'MIXRAT',3,4,0

              In this example, all fields except Z and MIXRAT are assigned an
           interpolation type of 2, a lower boundary treatment code of 3, and
           no free atmospheric levels are left uninterpolated.  The values
           assigned with the ICP TINTXL are used for Z and MIXRAT.

            Example 2:
            INTDT  = 1

              In this example, all fields are assigned an interpolation type of
           1, a lower boundary treatment code of 4, and no free atmospheric
           levels are left uninterpolated.  There are no exceptions.