This patch pertains to a problem that will cause the model to
hang if FDDA surface nudging is used.  The bug would likely
only occur with the surface nudging; not with atmospheric
nudging.  To tell which you are using look in your namelist
(mmlif) file:

This is using surface nudging and atmos nudging:

 I4D = 1,0,0,0,....
       1,0,0,0,....

This is using only atmos nudging:

 I4D = 1,0,0,0,....
       0,0,0,0,....

Obtain the patch file from:

   ftp://ftp.mcs.anl.gov/chammp/mm5v3_2_mppiopatch.tar

To install, untar this in the top level MM5 directory (the 
directory containing the configure.user).  Affected files 
are:

   domain/boundary/bdyin.F
   fdda/grid/in4dgd.F
   include/hdrv3.incl
   MPP/RSL/parallel_src/define_comms.F

The first file is related to the I/O problem noted with 
input for surface FDDA.

The second file fixes a potential problem with lateral boundary
input, but which shouldn't ever happen because 
the code does not ever intentally read past end of file on 
one of these files and if it did it would be an error 
anyway. The third file is needed by the first two.

The last file is a fix for an unrelated problem with the schultz 
microphysics scheme.

You must make mpclean and make mpp after installing this patch.

-Rotang, Nov 12, 1999