diff --git a/betacast.sh b/betacast.sh
index 013c296..e51b36b 100755
--- a/betacast.sh
+++ b/betacast.sh
@@ -673,10 +673,14 @@ if $doFilter ; then
     echo "Running filter"
     cp ${sePreFilterIC} ${sePostFilterIC}
     filtfile_name=${casename}.cam.h0.$yearstr-$monthstr-$daystr-$cyclestrsec.nc
-    ncl lowmemfilter.ncl \
+    (set -x; ncl lowmemfilter.ncl \
      endhour=${filterHourLength} tcut=${filtTcut} \
     'filtfile_name = "'${path_to_rundir}'/'${filtfile_name}'"' \
-    'writefile_name = "'${sePostFilterIC}'"'
+    'writefile_name = "'${sePostFilterIC}'"' )
+    if [[ $? -ne 9 ]] ; then
+      echo "NCL exited with non-9 error code"
+      exit 240
+    fi
   fi  # debug
 
   echo "done with filter, removing filter files"
diff --git a/filter/lowmemfilter.ncl b/filter/lowmemfilter.ncl
index a5b49dc..7415716 100644
--- a/filter/lowmemfilter.ncl
+++ b/filter/lowmemfilter.ncl
@@ -152,6 +152,6 @@ end do
 
 print("done")
 
-exit()
-  
+status_exit(9)
+ 
 end